My Mixergy IoT device – The start!

I’m loving my Mixergy tank, but one of the main issues is that the temp display is connected to the tank by a short wire. My tank sits out in the garage, so without consulting the app, it’s hard to know how much hot water you have.

The Mixergy control unit, showing charge, connection state and heating info.

Using my Home Assistant Mixergy integration and Siri Shortcuts, I’ve created something that my wife and I use. We can ask Siri to “check the hot water”. and it will reply with the current charge and water temperature. This is really useful as it works on our Homepods.

As fun as it is having to ask the computer for the tank measurements, I wanted to actually put a gadget into the bathroom, which would simply display the current charge etc.

Platform

When choosing the platform, there were a few considerations. Firstly, I didn’t want to spend any more money. I have small screens and MUC devices strewn around the office, so I wanted to make use of the stuff I already had. Secondly, it needed to use little or no power since it was going into the bathroom.

Years back, I purchased a WaveShare e-Paper display, but never found a use for it, until now. E-paper is great as it consumes no power when it’s idle. This felt look a logical choice!

For the MCU, I picked D1-Mini, which has an ESP8266 controller on it. These are great little boards for experimenting with.

Normally, I would be firing up a ZephyrRTOS project and writing some C, but this time I wanted to spend less time messing around and more time actually getting something finished. I’d heard about ESPHome and took a look. ESPHome is really cool platform that works with various MCUs and allows you to just cherry pick various components to build what you want. Put it all into a YAML file and install it. You can even update it over the air. It’s pretty cool.

It also supports ePaper! You’ll find the support detailed here, in addition to the wiring information. https://esphome.io/components/display/waveshare_epaper.html

To create a node for my Mixergy, I put together this little YAML file:

esphome:
  name: bathroom
  platform: ESP8266
  board: d1_mini

wifi:
  ssid: "<wifi_ssid>"
  password: "<wifi_password>"

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Bathroom Fallback Hotspot"
    password: "<update_password>"

captive_portal:

# Enable logging
logger:

# Enable Home Assistant API
api:
  password: "PWD"

ota:
  password: "PWD"

# Sensor
sensor:
  - platform: homeassistant
    id: current_charge
    entity_id: sensor.current_charge
    internal: true
  - platform: homeassistant
    id: coldest_water_temperature
    entity_id: sensor.coldest_water_temperature
    internal: true
  - platform: homeassistant
    id: hot_water_temperature
    entity_id: sensor.hot_water_temperature
    internal: true

# Display
font:
  - file: 'fonts/arial_narrow_7.ttf'
    id: font1
    size: 32
  - file: 'fonts/arial_narrow_7.ttf'
    id: font2
    size: 78
  - file: 'fonts/arial_narrow_7.ttf'
    id: font3
    size: 24
    
spi:
  clk_pin: D5
  mosi_pin: D7

display:
  - platform: waveshare_epaper
    cs_pin: D1
    dc_pin: D3
    busy_pin: D2
    reset_pin: D4
    model: 1.54in
    full_update_every: 30
    rotation: 90
    lambda: |-
      it.printf(100, 10, id(font1), TextAlign::CENTER_HORIZONTAL, "Mixergy");
      it.filled_rectangle(10, 50, 5, 130);
      it.filled_rectangle(50, 50, 5, 130);
      it.filled_rectangle(16, 180 - (130 * (id(current_charge).state / 100)), 33, 129 * (id(current_charge).state / 100));
      it.filled_rectangle(10, 180, 45, 5);
      it.printf(60, 51, id(font3), TextAlign::TOP_LEFT, "%.1fC", id(hot_water_temperature).state);
      it.printf(130, 88, id(font2), TextAlign::CENTER_HORIZONTAL, "%.0f%%", id(current_charge).state);
      it.printf(60, 162, id(font3), TextAlign::TOP_LEFT, "%.1fC", id(coldest_water_temperature).state);


This connects to the Home Assistant API and queries three of the sensors that belong to my Mixergy integration. It then renders this on the ePaper screen, showing a simple representation of the Mixergy tank, the hot and cold water temperatures and the percentage charge. It’s everything you need to know about the tank, at a glance.

Next Steps

Next step is to connect this sucker to a battery and experiment with the ESP8266 deep sleep. I think a five minute interval for refresh is probably enough (dropping to hourly at night), but connecting to WiFi and redrawing the screen consume a lot of power, so I’ll have to play around with it. Maybe I can use a small solar panel too as the unit will probably sit on a sunny windowsill.

I’d also like to make a little case for it, but I’ll need to do some research and see if there isn’t something I can just buy. This Waveshare unit is pretty common, so somebody must have made a case!

Then I’d like to add some sort of boost button, so we can charge the tank too. That’s further down the line as it will require changes to my Home Assistant integration…

Other Ideas

Given that a cloud API exists for Mixergy already, it would probably be possible to build a standalone unit that wouldn’t require Home Assistant at all. I’ve thought about this for my iOS shortcut – if I changed it to query the API directly, the Shortcut would be usable by anyone!

Smart Bulbs: my lightbulb moment?

I’ve always disliked smart lightbulbs.

Turn them off at the wall and you immediately question why you paid 1000% more.

I’ve held this position for years and years, until one day I came across a tweet by Troy Hunt where he used the words detached and Shelly1. This immediately captured my interest!

Now, I’ve had a few Shelly 1 relays installed in my house and they brilliant. So brilliant in fact I’d sort of forgotten about them. But when I heard about Troy was using them in combination with smart bulbs, my mind started racing.

Somewhere in the past 18 months, Shelly added a new Button Mode into their settings called Detached Switch.

Traditionally, you would install a Shelly 1 and use the button type of Edge Switch, which would allow the wall switch to turn the light on and off by flipping it. You can turn it and off via an app and the wall switch. Brilliant. Of course, the problem with smart bulbs still remains – turn the Shelly off at the wall and the smart bulb loses power.

This is where Detached Switch mode comes in! The relay is basically On and when you flick the wall switch, it raises an event and you then react accordingly.

With this combination, we can have a smart bulb and use a light switch!

Setting it up, however, does require jumping through a few hoops.

Setting it all up

Once the relay has been physically installed and setup, you can switch the Button Type to Detached Switch using the settings webpage on the relay. This disconnects the relay from the switched live.

For me, I use HomeAssistant, so I use the Shelly Integration to add the relay. When you open the device, you’ll see there are seven entities. The switch.shelly1_xxxx entity points to the actual relay, so toggling this switch will actually toggle the relay on and off.

The entity we’re interested in is the binary_sensor.shelly1_xxxx_input. This entity is connected to the switched live on the Shelly 1, so flicking the light switch will change this entity from on to off. By default, this entity is disabled in HomeAssistant, so you’ll need to enable it.

The Shelly Integration shows more than just the relay control

I purchased a LIFX IR bulb, one with a full color range and HomeKit support. LIFX setup was easy. The LIFX app found the bulb and connected it to my WIFI and HomeKit.

LIFX Nightvision A60 1200 lumens [B22 Bayonet Cap], Full Colour with  Infrared, Wi-Fi Smart LED Light Bulb, No bridge required, Compatible with  Alexa, Hey Google, HomeKit and Siri : Amazon.co.uk: Lighting

As I use the LIFX integration on Home Assistant, the bulb was added automatically.

I now had my smart bulb and my detached Shelly relay.

To connect these two things together, I used NodeRed. I use NodeRed for all of my automations. The automation is just two nodes. The first listens for state changes from the _input entity and it then toggles the LIFX bulb on or off.

Overall?

I’ve switched out all the a lot of the bulbs in my house to these LIFX bulbs as I picked up some refurbished dawn/dusk bulbs on Amazon.

It’s been around a month since I started converting all the bulbs and pendants, but in that time I’ve only had one issue and that was caused by one of the LIFX bulbs losing connection with HomeKit – which didn’t affect Home Assistant.

This setup is a great combination. The kids are can use Siri to turn on some of the lights and when we’re going to bed, the physical switch works as it always has.

There are some things I need to tweak, like brightness. For example, if we dim the light as we settle into the evening, we’re left fumbling for an app or asking Siri if we want the brightness back up when we turn the light on the following evening. I need to add some automations to just reset the brightness overnight or something.

My Mixergy Smart Hot Water Tank

I recently installed a Mixergy smart hot water tank into my new house, as part of a total renovation. I’ve been very impressed and wanted to share my thoughts on the product after using it for a few weeks.

The problem with hot water tanks

For me, the problem with hot water tanks two fold.

  • You’ve no idea how much how water you actually.
  • You don’t know how hot the water in the tank actually is.

My previous arrangement had a 210L unvented cylinder connected to a system boiler and controlled using a Nest Thermostat. In a setup which is repeated around the world, my boiler turned on at 5AM and heated the water for 30 minutes.

During the summer months, the water that came out of the tap would burn your hand. Sometimes we’d have water for two showers and a kids bath and other times, my shower would run cold towards the end. Never a great start to the day.

I tried to get a handle on this myself, by installing two temperature problems on the inlet and outlet of the tank and using the temp of the hot outlet to try and guess how much hot water we had. It worked pretty well, as it took some of the guess work out at bath time. That said, I still had to boil the kettle to top up the water as it ran cold from the tap.

I wanted to install more probes, so I could measure the temp at a few places, but the best I could manage was the positions of the various outlets. In the end, I had four probes attached to my tank, which helped, but it was never just accurate enough.

Why not just keep heating the water?

This is a solution that most people suggest – just heat the water for another thirty minutes in the afternoon, or boost it before you give the kids a bath.

For me, this just wasn’t what I wanted to do. Burning gas is something we need to stop doing for the environment and besides, why waste money heating water that’s already hot enough?

Enter the Mixergy!

I stumbled across the Mixergy tank quite by accident, whilst watching an episode of the YouTube show Fully Charged. The brilliant Robert LLewlyn had one of the tanks installed in his home as part of a trial and during the show he interviewed the creator of the product.

What makes the Mixergy tank different from other unvented cylinders is that it can tell you roughly how much hot water you have, as a percentage of the tank’s overall volume. It will also give you the inlet and outlet temperatures (like my crude attempt!).

In addition, it also heats the water by volume, meaning you only heat the amount of water you want, rather than trying to heat all the water in the tank at one go. This gives you much greater control. If you only need 100L of water during a normal day, the Mixergy tank will heat that amount. Better for the environment and my pocket.

The design also enables the tank to heat water more quickly, so in the event you do run out, you won’t have to wait too long.

Cost

Mixergy offer a few variations on the base tank, allowing you to access different heat sources.

Solar PV – The tank has an electric element installed as standard and you can have a dual element installed, which allows you to power the element using Solar power

Solar Thermal – The tank can come with a secondary coil inside, which enables you to use Solar Thermal

Heat Pump – All the tanks are heat pump ready and they require an exchange to be installed. This can be added in the future.

Hydrogen Boilers – As it’s an unvented cylinder, the primary heating coil will work whether connected to a gas boiler or a hydrogen boiler, so again, the tank is future proofed.

I vacillated between the solar PV and solar thermal options. In the end, I opted to just have the Solar PV version. I figured that Solar PV offered more flexibility and is something I’d be more likely to invest in, combined with a home battery. Mixergy also offer integration with Timer-Of-Use electricity tariffs and that offers a little more flexibility too.

When it came down to cost, the 210L Solar PV Ready Tank I ordered was a little over £1200. An equivalent 210L unvented cylinder can cost anywhere from £300 to £800, depending on all sorts of factors. The Mixergy tank itself is close to the top end in terms of size, insulation etc. so I reckon it was around £400 more.

Ordering and Delivery

I ran into a few bumps here. When I got in touch with them originally, they confirmed they could make delivery on my desired date, to coincide with the plumbing work. However, as we got closer to the dates, they reached out to tell me they wouldn’t make it in time. I was pretty annoyed to say the least.

They reached out again a day or two later to say I could have the slimline version of the tank, delivered on the original date at no extra charge. I rushed over to the house with an inch tape to confirm it would fit, with the required clearance. Thankfully it did and the order was confirmed.

The tank arrived. I must admit to being a little giddy with exceitment!

Installation

The Mixergy tank is essentially just an unvented cylinder with some additional technology built into it. This means the installation of the tank is the same as any other unvented tank. Our heating engineer installed it without any issue. We were short a few capping nuts and because they were a very unusual size, we had to contact Mixergy to get them. They did provide them, but fortunately, the engineer found a few he had and finished the job..

Being a smart home enthusiast, the heating engineer didn’t connect the thank to any heating controls. This is something I wanted to tackle myself.

I chose Tado for my central heating. This was for two reasons – it offers HomeKit integration and they have an API that HomeAssistant can use. They also have nifty smart thermostatic valves, so individual rooms can be controlled as zones.

As plumber installed my central heating in an Y-Plan configuration, I knew that control of the valves would be split, with the Mixergy tank controlling the hot water valve and the Tado would control the heating. The setup was straight forward and after a lot of reading and some triple checking, it worked. Thankfully.

The Tado control unit all connected to the two valves

The App

With the tank wired into the boiler and fully commissioned, it was time to connect the app with the tank.

This was very simple, thankfully. The tank comes with a Power Line adapter, so it was a case of plugging in the powerline adapter and connect that to my router. I then scanned a QR code on the adapter and the app connected to the tank.

I went through the settings and configured things like target temperature (how how you want the water) and the schedules. You can set the tank to simple heat a certain amount of water or you can have it maintain a minimum amount of how water. You can also boost the tank to a certain amount of water on an ad-hoc basis! Very nifty.

As it’s unvented, you can also setup the cleansing of the tank. If you don’t already know, unvented cylinders need to be heated to a certain temperature every few weeks to kill any and all bacteria in the tank. With my old tank, I just left the boiler temp very high to ensure that the water was always hot enough. To maintain a lower temperature and do a manual cleansing every few weeks would have required going into the loft, boosting the boiler temperature and running the water for an hour. It was simply easier to take the lazy approach. Mixergy solves this by automatically managing this process. You choose the days and times that you want it to occur and it will use it’s best judgement to run automatically. They recommend you do it on days when you might want a lot of hot water anyway, so I opted for the days we bath the kids.

Another nice feature of the app is that it can give you energy consumption information!

First Showers

After our first night at the house, I fired up the app the following morning and boosted the water to 30%. I really had no idea how much water we’d actually need. 30%, as my wife will tell you, was not enough as her shower ran cold.

I think it was a combination of the flow rate being at maximum on the shower, the thermostatic valve not being calibrated and the fact that 60L isn’t enough water for two showers!

By reducing the showers flow rate just a little, we now get by on a charge around of 60%. We do too thi

The API + Home Assistant

Another factor in favor of Mixergy is the fact that they offer an API for interacting with the tank. Once I had the tank installed and connected, I spend an hour exploring the API and seeing what sort of information it returned. I was able to add a basic integration into Home Assistant that returned some basic information about the tank’s status.

I’m hoping to get this added into the Home Assistant platform, but I’ve a lot of work ahead of me!

You can check this integration at https://github.com/tomasmcguinness/homeassistant-mixergy

Final Thoughts

Overall, I’m very, very happy with the Mixergy tank. At this moment in time, I don’t have any figures to really see if I’m saving money.

My previous energy supplier, EON, only had bills available for three month blocks. For example, From 26th of April to the 26th of June, I used 112m3 of gas. I’m guessing we wouldn’t have had the heating on as we were into May, so basic division estimates around we used around 38m3 a month. Looking at my Octopus data, June for example, my gas usage was a little under 30. Of course, we had a gas hob in my previous property, which doesn’t factor in this time.

Of course, as we head into the winter, it will be ever harder to estimate, but my gas concern is over the entire house, and I hope the combination of the Mixergy tank and the Tado will reduce my overall gas consumption. Good for my pocked and good for my kid’s futures.

Automating our dual fuel towel radiator

As I explained in my earlier post, heating our bathroom, we installed a dual fuel tower radiator. A dual fuel radiator is one that can be heating by both our central heating and an electrical element inside the radiator. This allows us to dry our towels without having to turn on the central heating, something that is very useful in the summer months.

The dual fuel element connected via a spur in the wall

I opted for a dumb element, one that has no controls built into it. There are plenty of elements on the market that offer controls, Bluetooth integration and that sort of thing, but they can be very expensive and require dedicated apps etc. I wanted something I could add to my Home Assistant installation, something I had full control over.

My plan was to use a Shelly 1PM to allow me to turn the element on and off. Shelly offer a wide range of smart relays. I’ve used several of them to control lighting and I’ve found them reliable and easy to setup. The 1PM model also offer power monitoring, so I can measure the power being consumed. This isn’t really necessary, but I thought it might be useful to measure this and record the long term power consumption in order to understand how much the radiator costs to run.

Installation

When the electrician was installing the element (has to be wired into the wall by a qualified electrician as it’s in the bathroom) I asked that they leave access to the wires beside the fuseboard.

Supply and load wires as left by my electrician

What they left was exactly what I wanted.

Next step was to add a double pole, fused isolation switch. I wanted to be able to knock off the radiator and Shelly relay in the winter. I could have used the RCD directly, but I liked having a dedicated switch.

I added a second backing box to house the isolation switch. I knew a single box wouldn’t hold the switch and the relay. I put a 5A fuse into the switch.

With the double pole switch installed, I then wired in the Shelly. I didn’t need to use the switched life or L1, so installation was very simple, with the load (the element) going into 0 connection.

Once I powered up the Shelly, I connected it to my WiFi network. To my delight, Home Assistant detected it and allowed me to add an integration without having to do any MQTT customization! I haven’t controlled Shelly devices with anything except MQTT, so I decided I’d try this integration out.

How the Shelly 1PM shows in Home Assistant (I renamed the relay switch)

I switched on the relay and after a few minutes the radiator began to warm up. Success!

Automation

With the relay working as expected, I added a simple automation to NodeRed

When the towel rail is turned on, this automation will start a timer and automatically turn the element off after one hour. I receive notifications when this happens.

I’ve not controlled anything like this before – it’s one thing if a light automation fails to turn off a light, but if a 600W element is left on for hours and hours bad things might happen. The notifications give me some piece of mind. I’ve never had any reliability issues with NodeRed or HomeAssistant, but better to be safe than sorry.

Next Steps

I’d like the towel rail summer automation to be more automatic, removing the need for manual intervention at all.

My first thought was to use the humidity sensor to trigger the automation e.g. if humidity rises by a few % for a few minutes, then somebody is probably having a shower.

Another option would be to measure how much water being consumed over a period of time. If it’s lots, this would give a indication that a shower or bath is in use.

I’ll go with manual for the time being, mostly to gain confidence that my automation is working.

Making a dumb light switch smart

A few months back, when planning the rewiring of our house, we decided not to include any switched 5A sockets; you know the kind of arrangement where a switch on the wall can turn on some floor lights and lamps in a room? If you want light, but something subdued, it gives you an alternative to turning on the “big light”

We had this arrangement in our previous house and we used it all the time, but for some reason, we opted to do without in our new house. Really don’t know why.

After living in the house for a few weeks it became painfully obvious that we had made a mistake. Yes, we can turn the lamps on individually, but it’s just so damn convenient having a switch!

I have WiFi smart plugs, which I could use, but these just make matters worse as you usually need your phone to turn on and off the lights and aren’t great for guests.

I began thinking of how I might make a dump light switch turn into a smart light switch.

I had a flash of inspiration, when I began thinking about the Aqara light switches I have (in boxes now) and how they had a battery powered model. They are just a push button switch with a Zigbee module. I wondered how I might break one of those apart and wire it in to the my MK switch. I did some googling and I found a YouTube video which showed exactly that – the only downside was that they were using a push switch!

Then I had the light bulb moment; Contact sensors! I did more googling and sure enough, loads of people had just connected standard Zigbee contact sensors into an existing light switches. It was the perfect arrangements. Contact sensors have simple magnetic reed switches, which send the appropriate of open or closed. Swap the reed switch for a mechanical switch and the operation should be exactly the same!

An Aqara contact sensor, opened up

I opened up one of the Aqara contact sensors I had, and inside, I found a small little battery powered module. On the reverse, the reed switch was visible. Please forgive the photo. I didn’t realise it was that blurred.

The reed switch is operated by an external magnet and indicates if the contact is open or closed
I removed the reed switch and added a wire to each of the contact plates

I removed the reed switch and put two wires onto the contacts. After pairing the device with Home Assistant, I was delighted to see that touching the wires put the sensor into a closed position. The next step was putting into a standard switch.

Put the contact sensor into a real switch

That was easy. The switch now successfully opened and closed the contact sensor. I originally used the normally open P1/COM connectors on the switch, but Home Assistant equates “open” with on, so I ended up using P2/COM, so when the switch is Off, the contact is closed.

With the switch working as expected, I created a simple automation in Node-Red to turn a smart plug on and off. Nothing fancy. When the contact is open, turn on the light and when closed turn off the light.

My thoughts turned to actually then installing the light switch and whether or not the zigbee signal would get through the metal backing box of the switch.

Please don’t do anything with electricity without first isolating at the fuse board. If you’re not comfortable doing this, please don’t. Electricity can kill.

I started by opening up the exiting one gang switch and the wiring was as expected. One switched live and

The existing single gang switch
The two gang switch in place
It works!!

Heating our bathroom

The bathroom in our old house was cold. Really cold. It had two external, solid brick walls, and the room was tiled floor to ceiling. We had a rubber floor covering, so at least you didn’t suffer from very cold feet.

We had a lot of condensation, which unfortunately led to some mold. We tried to mitigate this by installed a large ceiling extractor fan over the bath, which helped a little, but one of the biggest problems was the radiator – it was just too small.

In our new house, we weren’t going to make the same mistake!

Our plan was two fold; we would install underfloor heating and a towel rail. Our new bathroom has three external walls, but as it’s cavity wall, it won’t be as cold. We aren’t tiling the entire room this time, so the walls shouldn’t be as cold.

How much heat do we need?

The first port of call when trying to determine our heating requirements is a BTU calculator. There are dozens of these online and they use crude bits of information to determine how many watts of heat you will need to warm a space.

I’ve checked a few calculators, putting in three external walls, one window, insulated ceiling and cold floor and got a result of around 1500 watts.

As we had chosen a tiled floor, we decided that we’d use a combination of a towel rail and underfloor heating (UFH). The towel rail to dry our the towels and the UFH to ensure the tiles weren’t too cold in the winter!

Unfloor Heating

We figured that starting with the underfloor heating was the best bet.

UFH comes in two types, wet and electric. Wet involves a series of pipes in the floor that are heated using the central heating. Electric uses a long wire, which gets heated, well, eh, electrically. As we were only heating a small space, the electrical UFH was the better option. It also is pretty easy to install as it doesn’t require a plumber and a complex manifold. This meant I could do it.

There are three parts to electric UFH. First, there is the heating wire. This contains the heating element. Then there is the temperature probe, which measures the temperature of the floor (and optionally the air) and lastly, there is the control unit, which turns the heating wire on and off and regulates the temperature.

The heating element

I found that the heating element comes in two forms. One is a loose wire and the other is a mesh mat, which has the wire attached. When dealing with a really unusual room, the loose wire is recommended, but it’s much more involved in putting it down. The mat, on the other hand, offers an easier solution, but it can be difficult put down when you’re dealing with irregular layouts. You can cut the mat and even remove the wire completely if you want to get into an area where the mat isn’t suitable.

For my bathroom, I was pretty much covering a rectangular area, so the mat made the most sense. They seem to all come with sticky tape, so you can literally just stick them down.

When it comes to these heating elements, it’s worth pointing out that they come in fixed lengths and the wire itself cannot be cut, so it’s impossible to lengthen or shorten it. More on this later!

The temperature probe

This is probably the simplest big. It’s just a long wire with a little bulb at the end. They are usually put into the floor and measure the temperature the floor.

The Controller

The controller turns the heating on and off to keep the room at the desired temperature. As I’m a smart home nut, I wanted to have some ability to control and manage this remotely, so I opted for a Heatmiser neoStat-e V2. This unit is designed for electric UFH and supports 16A mat (way more than I’d need). Heatmiser units can also be connected to an optional hub for remote control. Whilst I may never connect it up, it’s nice to have the option.

The controllers all seem to come with a temperature probe, probably because they are calibrated for them.

Getting Started

I started by drawing out the bathroom floor and blocking out where the shower, bath and toilet would be. These occupy floor space, so heating them made no sense.

My plan to lay out to mat

I figured I needed to cover approx 3sq/m. You have to leave 10cm gap between the mat and any walls etc.

We knew that the towel radiators would offer between 600 and 1000 watts of heat, so I then choose a mat which provided 200 watts per square metre. A total of 600W.

The mat I bought was a ProWarm model and I got it from https://www.theunderfloorheatingstore.com/

When the mat arrived, however, it was for 3.5 square metres!! The mat is 50cm wide, so this equated to an extra meter of mat, which was going to be lots of extra wire. Initially I panicked, but then my bother-in-law pointed out that I can simply cut the wire off the mat and lay it down any way I want. I looked at my floor layout again and decided it would work and I could just heat heat either side of the toilet. An extra 100W of heat for free!

The electrician got the important part setup for me, with a fused spur and 35mm backing box for the controller.

The electrics outside the bathroom
The final arrangement with power running from the fused spur up to the box where the controller will live.

The white conduit holds the mat’s power cable and the temperature probe. Heatmiser recommend that the probe can be accessed and removed in the event it fails. I used the white conduit down the floor and then a 7mm flexible black conduit, which would under the tiles.

Electrician added outlet for radiator and I took the UFH wires through the same spot
I stuck the conduit down to test how easy it would be to remove and reinsert the probe.

To test this setup would work, I stuck the black conduit down to the floor to simulate it being in position in the finished floor. I think removed and replaces the probe twice. It was pretty easy and just required a little pressure to get it moving. In the event the temperature probe did fail, I had *some* hope of being able to replace it.

The next step was to put down concrete backing boards on top of the floorboards. The builder recommended this as it would reduce movement in the floor and prevent the tiles from cracking.

The concrete backing board on top of the existing floorboards

At this point, I was very conscious of what the finished floor level would be. The backing board, the mat and then the tiles. One problem at a time.

The tiler, who was going to put down the self levelling layer over the mat asked me to make sure there were no gaps around the edges of the room. He said the liquid would simply pour through the holes making his job very difficult. To tackle this, I used a mixture of expanding foam for the larger gaps and decorators caulk for the smaller gaps.

Foam to seal the edges
Caulk in the joints of the backing board

I also put caulk into the joints of the backer board. Belt and braces.

Next, I had to cut a whole in the floor and locate the bath waste. The plumber had left a mark on the subfloor, which *thankfully* I had photographed!!

Some masking tape and a distance from the wall

The multitool came in handy, yet again. I marked out the positions and cut the backer board….

X marks the spot!
The moment of truth!

With the bath waste hole cut, I turned my attention to the heating mat. I’m not going to lie. This really, really frustrated me.

My mistake was not understanding that the mat could be laid either side up. I had initially unrolled it thinking the tape strips (for sticking it down) were on the bottom; which they weren’t. I had already cut the mat when I realised this, so I flipped the mat over and carried on. When I’d unrolled it, the extra amount was *way* more than the 1m I was expecting. It was closer to 1.25m

Long story short, after much cutting and thinking (99th percentile for spatial reasoning at age 17) I had it down.

Better coverage than I expected

It’s a little rough, but I got better coverage than I expected. Once it’s stuck down and covered with the self levelling stuff, nobody will know except me, my wife and the tiler. And you, dear reader.

Next job was to sink the wires and temperature probe, so they didn’t stand proud above the mat. I marked it all out and using the multitool, I cut grooves for the power wire and probe conduit. I think used a chisel to cut out the groove.

It was slow work, but I got there in the end. Of course, by cutting through the backing board, I’d added an break in the mat, but hopefully this wont’ introduce any more movement.

The temperature probe in position. It’s curved to take it closer to a heating wire.
I taped down the mat to ensure it didn’t stick up too much

You can see along the shower tray that I cut the wire away from the backing mat and just stuck it down, ensuring I left spacing between he wires. The tiler then came and put down the self levelling. I was initially going to do this myself, but I reason that the tiler would be much happier working off a surface he was responsible for, rather than my amateur effort.

The self levelling compound in place! You can see a few places where the mat pokes out about the surface

After 24 hours, the floor was ready to walk on. I checked the resistance of the mat and temperature probe for the umpteenth time and all was good. The tiler then set to work.

The fabulous tiles my wife picked out!

The Radiator

Not much to say here as you probably know what a radiator is. Powered by your central heating, this is the most common way of heating a bathroom. This time around, we also wanted to install a dual fuel radiator.

What is Dual Fuel?

As towel radiators are connected to the central heating, you are guaranteed of a nice warm, dry towel during the winter months, but once you get into the summer, the radiator is never hot. This can leave towels damp and lead to excessive moisture issues.

During the course of my research into moisture issues in my previous bathroom, I discovered something called Dual Fuel radiators. Essentially, you can install an electric heating element into the radiator, so that during months when the central heating is off, the radiator can be heating up electrically!

The operation of the element requires a manual step where you essentially switch from water heat to electrical heat. In the spring, once the central heating is off, you need to shut the radiator valves and open the little “bleeded” valve at the top. You can then turn on the electric element. In the autumn, when it’s time to switch back, you operate in reverse.

Things, however, turned out to be a little tricky when it came to the dual fuel element. Regulations here in the UK, have strict rules about electrical items and water and dual fuel elements are governed by this rules. Anything electrical typically has to be 60cm away from the edges of showers, baths or sinks. We confirmed this with our electrician just to be sure.

Sizing it

With 700W coming from the floor, We only needed 800W to make up the difference. The output of a radiator is measured in two ways – BTUs and Watts. The output also depends on the temperature of the water running through the system and the temperature difference between the radiator and the room it’s heating.

We also only had 75cm of space on which to hang the radiator and we had to allow at least 10cm for the spur.

We needed something that was around 500mm wide, black, not too tall, output at least 800W and supported dual fuel. We’d left it quite late to order a radiator, so our options weren’t actually that large. I found something, which suited our needs perfectly and was able to get it delivered within a week.

We ended up with a Radox Hercules. A good strong name for a radiator. I ordered it from Designer Radiator Concepts. There was some confusion around delivery date, but we were able to get it within a couple of days. They provided the valves and dual fuel kit.

When the plumber came to hang the radiator we discovered that a part was missing – the t-piece. This mean the plumber couldn’t position the tails (a fancy way of saying pipes) of the radiator correctly. He fixed the value on one side, but not the other.

The rad on the wall. It looks really nice. Ignore the pipework.

The layout worked out very well. The plumber was able to hand the radiator, centered on the wall. By placing the valve under the radiator as opposed to outside (which I hadn’t even thought of), the rad size worked perfectly!

Backing box for spur in relation to the radiator. Perfect!

Unfortunately, a large lump of plaster fell off the wall when the electrician was trying to cut out the box. Once I had positioned the mat’s wire and probe, I used some bonding to stick a lump of plasterboard into position.

Fixing the wall

Next steps

Once the first fix is finished and the radiator plumbed in correctly, I’ll write up another post covering the setup and control of the underfloor heating and go into some depth on my plans to control the dual fuel element using a Shelly 1 relay.

Stay tuned!

Moving a wall to create a bigger bathroom!

When we purchased our house, one thing that we didn’t really like was the small bathroom.

The layout is pretty standard for the type of house, with an airing cupboard and W.C. over the garage.

The existing layout of the bathroom

We knew we wanted to retain the bath, for the kids mostly, and we knew we wanted a separate shower. The airing cupboard was redundant as the hot water tank was moving down to the garage.

With that, we formulated a plan. Knock the walls between the toilet and the bathroom and move the wall between the bathroom and bedroom 4, removing the airing cupboard in the process. Bedroom four was going to become an office, so losing some space wasn’t a big deal. We did check it would still fit a single bed, in the event we needed to return it to a bedroom.

The plan (I’ve got no Paint skillz)

This seemed straight forward on paper, but we have some considerations:

  • Position of all the waste pipes for bath, shower, sink and toilet
  • Different floor levels between bedroom 4 and the bathroom

The waste and floor levels

We spoke to the several plumbers about the waste and were assured that once the toilet was on the outer wall, the rest of the waste was no issue as there was enough of a fall across the floor for the other waste.

The floor levels turned out to be simple too. The floor joists of the bedroom were sitting on a wall and provided no support to the bathroom. We knew we could safely cut back the floor joists, which was great news!

Getting Started

Getting started is always both exciting and terrifying. First thing, was removing the bath.

Our beautiful avocado green bathroom!
The bath, in all it’s glory!
Bath is gone, but we discovered a lot of rotted floorboards

My father in law helped with capping the water feeds going to the bath, so we could keep the water turned on.

With the bath taken out, we tackled the shower and the plumber removed the radiator and existing pipework. We left the sink in place as it was handy to have in the short term.

Taking down the walls

With the bath gone, it was time to take down the bedroom wall. I checked with both the builder and a structural engineer to ensure the wall wasn’t load bearing before we tackled it.

I enjoyed this part as I basically took a hammer to the wall 🙂

A whole in the wall 🙂

I then just cut and pulled off the plasterboard on the bedroom side, exposing the studwork, before moving to the bathroom side and finishing the job. It was more involved on the bathroom side as the tiles made it more difficult.

With one side removed, I did a time lapse of the other side being removed
All the plasterboard is gone!

With the plasterboard all removed, we had a much better understanding of the structure of the floor. We then picked the position for the new wall, which was under the “crank”, visible at the top of the picture. This made the bedroom smaller, but actually resulted in the window being centered in the room. It did leave a small “kick” in the bathroom, but we needed that as the electricians and plumbers had taken all their wires and pipes up from the garage below.

The plumber and electrician were great in how they ensure all pipes and wires remained inside this little space and made sure that we could move the wall without issue.

Removing the WC

With the bedroom wall taken back to the stud work, we then moved onto the toilet walls. We followed a similar process, removing all the tiles and plasterboard first. The loo was easy to remove, thankfully.

I put the timber in the wrong place 🙂

We then removed all the remaining studwork. I didn’t set my time lapse up for this unfortunately, but it proved a little tricky due to the way it was holding up part of ceiling. We took our time and slowly, but surely, we removed the rest of the timbers.

The wall is gone!

Then came time to cut back the joists. I must have measure this ten times!

With the joists cut back and all the walls gone, the bathroom did feel very big!

The new wall

Putting up the new stud wall was straight forward, with only one tricky part in the corner to deal with. We created a simple frame and then put the studs and noggins in, trying to space them out as best we could.

The finished product.

You can see in the image above the large timber along the top, which is holding up the roof. We were able to attach to that and the joists below. We then fixed one side into the wall.

The problem!

As no DIY can go without a problem, we hit ours. I’d chosen 38mm thick timber for the studwork, but during the first fix, the plumber pointed out that the concealed taps need a depth of 50mm. This mean they would protrude more than 10mm off the tiles!

The builder offered a simple solution, which was to use two sheets of plasterboard to make up the difference. I’ll post some pics of the bathroom once it’s tiled and fingers crossed this will work!

Plastering the bathroom

With the wall in place, we removed all the timber and took out the sink and remaining odds and ends.

Ready for the processionals!

The plasterer then boarded and skimmed the walls. We were tiling half height around the room, so we didn’t need it all skimmed. He also pulled down the old ceiling and put in some extra noggins to sure up the ceiling.

I also created a little channel in part of the stud work, which ran from the ceiling to the floor, essentially connecting the garage to the loft. I thought this might be handy in the future if I ever need to run more cables into the loft.

All boarded and plastered!

Sound Proofing

The builder mentioned it would be worth putting some insulation into the new wall to give some sound proofing. I hadn’t considered that but it was a good idea. The lack of a brick wall would have meant you’d hear everything between the two rooms.

The plumber had finished his first fix and the electrician had done all the wiring they required, so I was free to go ahead.

I picked up a roll of acoustic insulation from Wickes and installed into the walls. It was Knauf earthwool.

I take pictures so I know where everything is!

The acoustic insulation came in a roll, so I just measured and each strip with a pair of scissors. I pushed it in behind the cables and pipes.

The acoustic insulation in place.

Final plastering

Insulation done and wires pulled into the right places etc, the plaster came back and finished the wall.

Not very exciting!

All Done

When we stand in the (unfinished) bathroom now, we’re happy with our decision. It means we can have a free standing bath that we want and we can have a walk in shower.

Aside from the mistake with the studwork not being thick enough, the project went off without any major hitches.

Again, a big thank you to my brother-in-law and father-in-law for helping with the work and giving me the confidence to give it a go.

I’ll do another post covering the tiling and fixtures in the bathroom. I’m going to be putting down some underfloor heating too and I’ll do a post covering that.

Insulating our suspended floors

As we’re renovating our new house, one of the things I wanted to do was to insulate the floors of the downstairs rooms. When we renovated our first house, not doing something about the floors was something I regretted. At the time, we didn’t think about it, due to the looming deadline of our first child’s arrival and once the engineered floor went down, our hands were tied.

This time around, I decided it would be something worth doing.

The insulation and materials

I spent quite a few hours researching the insulation of suspended floors and settled on the use of PIR. This is a solid foam insulation that has foil backing. It’s more efficient than rock wool, meaning you need less of it for the same level of insulation.

I used a few insulation calculators and came to the consultation that 60mm of PIR would be enough to meet building regulations. I set myself a budget of £500 and after shopping around, I found some 75mm PIR. I reckoned I would use around 12 sheets, so I purchased 14, for any wastage etc. In terms of brand, I went for the cheapest one that had the desired U-value. This happened to be Ecotherm.

I ordered 25×38 tanalised timber lengths from Wickes, which would be cut into 6″ lengths to serve as batons for the insulation.

For screwing down the floorboards, I went for No.8 (4mm) x 50mm screws. I estimated 1400 screws (I was short) so I end up with nine boxes and used seven and a half.

Tools

I also got some expanding foam, for sealing any gaps and rolls of foil tape for sealing up all the joints in the insulation. I already own a proper foam gun, so I just needed some canisters of foam.

For cutting the insulation, I ordered an Insulation saw. This doesn’t teeth like a normal timber saw and the results were nice clean cuts (albeit not straight!) with no dust.

I purchased this floorboard lifting tool to try and make the job a little easier.

I used a DeWALT Cordless drill and Cordless Impact Driver for pilot hole drilling and for driving in the many, many screws.

To speed up the pilot holes, I picked up some special drill bits. These include a special countersink head, so you get two for one in terms of the pilot holes. I didn’t have this when doing my deck and that involved switching from drill bit to countersink bit over 1000 times!!!

Image 1 - TREND CRAFT PRO 5PCE HSS DRILL & COUNTERSINK SET CR/QR/CS/SET

I treated myself to an Evolution mitre saw. I’ve wanted to add a mitre saw to my inventory for quite some time and this seemed like the perfect excuse. This saw was recommended as best value for money on several websites and it offered a large 80 x 300mm cutting size, which would be perfect for all my DIY needs.

I got an Evolution 255 SMS+

During the course of the work, I also treated myself to a DeWALT Multitool as well. I opted for a battery powered one to provide me with future flexibility.

This is a battery powered multitool, which I think will come in handy for other projects too.

The front room aka the practice room

The room itself was 3.6m x 3.6m with 10 floor joists and 26 floorboards. It had a small bay window. My plan was to give this room a go and see how difficult it would be. If it turned out to be too difficult, I could abandon the project without too much damage. If all went well, I would tackle the large back room too.

Image 3 of 20 for 59 Naseby Road
Before carpet lifted and radiators removed

The floor boards in the house dated back to around 1960, but were in excellent condition.

The electrician and plumber had already lifting some of the boards during their first fix, so we had some space to work with.

I made a time lapse of the job lifting the boards. I roped my father-in-law into help.

It was really difficult work. The boards themselves were tongue and groove and this made it really hard to cleanly lift them.

We used a mixture of hammers, crowbars and the lifting tool. After more than four hours, we had them all lifted.

Floorboards lifted (broken shadow wall visible in the centre)

The joists were in amazingly good condition, which was nice. A part of the shadow wall had collapsed, so we made a note to fix that. You can just make it out in the picture. One of the joists was also resting in the airbrick’s space, so we made a note to fix that up too.

First step was fixing the batons. These were 6″ long, with two screws, one at either end.

My father in law always created a little jig to help with the batons.

I invested in a special insulation saw, which minimised the dust generated (basically none)

By working in short lengths of 1.2m (cutting the boards width ways) we achieved a very tight fit. Some of the edges weren’t straight and sometimes the manufactured edge bowed inwards, but overall they fit very snugly. We also made sure to fix up the fallen shadow wall using some loose bricks. I mixed up a small batch of mortar to help ensure our repairs didn’t fall down again!

You can see the noggins installed

Once we had installed all the PIR, the next step was taping up the filling any gaps with expanding foam. Along the edges, where the spaces were wide, we cut and inserted thin strips of PIR, before filling the remaining spaces with foam. I also made sure to fill any of the larger gaps between the joists and PIR and in some of the large seams where PIR met each other.

Once the foam had set, we then we about taping up all the joints. I had 100mm wide foil tape which we covered the joists with, sealing up each seem. I got a cheap seam roller to help with this as I wanted to make it as airtight as possible.

WIth all the joints taped, I then laid them out to ensure every fitted and was spaced out. Then starting at the end, I worked backwards. My process was this:

With all the boards laid out I started work on the three boards to at the far end of the room. These were boards, 26, 25 and 24. I lifted them out, hoovered up any dust, taped up any marks or mistakes in the foil tape and then laid them back down. I then lifted boards 23 and 22. This showed me where the joists where, and using my square, I drew a pencil line onto the boards. I then drilled pilot holes and screwed the boards down. I wasn’t very particular where I drilled the holes, but I made sure to put two on either side, avoiding any existing nail holes.

I was complicated in places by the fact the electricians and plumbers had cut some of the boards for access, but I did as good a job as I could.

I continued this process all the way back along the floor until the final three boards, where I worked the other way. I did this because the board right along the wall wasn’t cut very well and was difficult to adjust. The tails for the radiator also came up through this board and I wan’t sure of their eventual position (radiators were removed for painting) so I needed to leave myself access so I can make good any gaps once the tails are reconnected.

Laying out the floorboards before screwing them down

All told, I think it probably took me five or six hours to screw them all down. I had plenty of practice when this as I installed a cedar deck at the back of my old house. I didn’t have the benefit of the countersink bit back then, so the 1200 screws took a long time with a lot of bit switching.

It took 600 screws to put down this floor.

The back room aka I’ve enough confidence to do this again

I was happy with the outcome on the front room, so I moved onto the bigger back room. This room is the same width, but about 1.5m longer.

This time around, I decided for a different approach when lifting the floorboards. The big problem was the tongue and groove boards. We knew they’d be difficult, but I underestimated how difficult. We broke so many of the groove and tongues that I figured, why not just cut the tongues first? This should make lifting the boards much easier.

I considered using a circular saw for cutting the tongues, but decided against it (blade thickness and cost of mistakes). Instead, I opted for a multitool.

With lots of help from my brother in law, we cut the tongues and lifted the boards. It was *mush* easier this time around. Using the big rough tool, we would just work up and down the board popping it up. We still needed the hammer along the sides, where we couldn’t fit the tool.

Progress was very swift compared to the front room.

My brother-in-law did most of the work, but don’t tell him that 🙂

I numbered the boards in the same way, this time I wrong on the top of the board, rather than the underside. There were less small boards and no funny angles to contend with. The only problem was that the length of the boards made them a little unwieldy.

It went really well, until we hit the fireplace. Marble and fixed into the brick work.

The marble fireplace
Dropped it off the wall onto some underlay. It was very, very heavy
I hit it a lot with a hammer to break it up. A hammer that we actually found under the floor.

Once the fireplace was out, we removed the last few floorboards.

With the floorboards up, I checked the pipe work was all insulated, taped the joints and added some support to the pipes by using wires fixed to the joints. The shadow wall was in good condition and I just fixed some of the slate spacers where there was movement.

It was then I realised that I should have ran speaker wire from the TV location to the the opposite wall! I’d completely forgotten to do this in the front room, much to my annoyance.

In addition to an ethernet cable (who knows!) I pulled four speaker wires and fed them through some conduit. If I ever add surround sound to this room, I’ve got four speakers covered.

Then it was a case of following the same process as before, attaching the little noggins and cutting the insulation to size.

Work in progress!
All board down and expanding foam put into the gaps.

With it all foamed, next came the tape. I got a different brother-in-law to help with this. I made a little time-lapse of this too.

As with the front room, I moved all the floorboards back in and laid them out to ensure even spacing. Having the number on the top of the board was much better as I could easily see any mistakes.

This time, with the help of my wife, I worked four boards at a time, piloting and screwing down. It took about six hours to get them all screwed down. For this floor, we used around 900 screws. I had estimated 1400 for both floors, so the wife had to make an emergency trip to Screwfix!

We had the same issues with the radiator tails, so those boards remain uncut. I’ll sort that out once the walls are painted and the radiators are back on the wall.

All screwed down!

Conclusions and lessons learned

I consider this project to be a success. Sure, it took longer than expected, but I think we’ll reap the benefits of this during the winter months.

In terms of materials, I ended up only using 10 sheets of insulation. I think that’s because of the joist thicknesses and the area occupied by the fireplaces in both rooms. I will probably try and sell the four sheets as they are in pristine condition.

Could I have used thicker insulation? I think the argument here is that more is always better, and whilst I agree with that, cost has to be factored in. I could have spent £700 or £800 on 100mm thickness boards, but the extra thickness probably wouldn’t have made much difference. The house is old with cavity walls, so the money might be better spend elsewhere to get more bank for my buck.

In terms of the actual work involved, cutting the insulation was probably the part I got least right. It was very tricky to make straight cuts and more often than not, we had to trim the sections of insulation to make them fit. No matter what approach we tried, we always almost always had a wonky cut.

When it came to lifting the boards, the second approach of cutting the tongues worked much better than just trying to force the boards up. I wish I’d done that in the front room too. Not only did it make lifting the boards much easier, it made it easier when laying them back down. Cutting the tongues was an option since we weren’t planning on exposing the floor, so any marks and gaps will be hidden by carpet or floating floor. I toyed with the idea of sanding and varnishing the floor, but as we have a beautiful hardwood floor in the hallway, we decided we’d probably carpet anyway. I

I’m worried about the central pipes freezing in the winter. They were lagged by the plumber, but I’m still a little nervous. I’m going to drop two temperature probes into the cavity underneath and use that to give me a reading of the temp. If I drops below zero, I can always have HomeAssistant turn on the heating for 15 minutes or something during the night to stave off the cold.

The other concern is any condensation. I took care when taping down all the joints and when foaming the gaps, so it should be unlikely, but I took the easier option, so if the joists do rot, I’ll naturally blame myself for taking the easy option 🙂

I’m also annoyed at myself that I didn’t run speaker cables in the front room. I’ve considered trying to fish cables under the floor, but the shadow wall would make that very difficult, so I’ll just leave it for now.

Overall, we won’t feel the effects of the insulation until winter hits. We won’t know what exact effect it will have since we won’t have experienced the house in the winter, but I’m very confident that the insulation will make the house much warmer!

New House – Technology Choices

I’ve recently bought a new house.

We completed renovated our first house and, in the process, we made an awful lot of mistakes. Don’t get me wrong, we got an awful lot of things right too, but we’ve always had some annoyances. These were born of inexperience and naeivaty.

With this new project, we have an opportunity to do another renovation and we can put some of the lessons learned into practice.

I want to write a few blog posts covering the renovation, so to kick that off, I want to start with technology. Obviously.

Readers of my blog will know I love smart home technology. I got to try out various bits of kit in this house, such as Den Switches, Shelly Relays and Aqara odds and ends. I build temperature sensors for my hot water tank and a salt sensor for my water softener. I learned about Home Assistant, MQTT, Z-Wave and Zigbee. I installed and then removed a Nest camera. I upgraded my home network with Ubiquity gear and learned about PoE and cable crimping.

What will I not do again?

Nest Thermostat

This was the first piece of home technology I ever purchased. It was great to begin with, but after a few weeks, I turned off the “learning” mode. It was turning on the heating at random times during the night, when I felt it just wasn’t necessary. Another problem I had was that hot water could only be operated in blocks of 30 minutes or more. During the height of the summer, 10 or 15 minutes would have been enough.

The smart home/away feature was great and it has some limited interaction with Home Assistant. Google then killed off the API program, so all that support went away. I decided I wanted something just a little more flexible.

Cloud based cameras.

When we first moved in to the house I had it wired for security cameras, but against my instructions the electrician put in Coaxial instead of ethernet I wanted. When he then asked for £1000 to install the cameras, I politely declined. At around the same time, Maplin was going into administration, so I picked up a Nest Outdoor camera and two indoor cameras during their sale.

I was very impressed with the Nest outdoor camera’s quality, but it always felt slow to access and the movement notifications always had a noticeable delay. I always thought it was dumb that I was streaming the video from a server (probably in the US) when the camera was *literally* connected to the same WiFi.

After Nest released their video Doorbell, I picked one up and installed it, figuring I’d stay in the same eco-system. This was when I really started to notice the delay in notifications e.g. doorbell would ring and 20 seconds later my phone would chime.

Then there was the cost for storing the video. It was costing me over £100 a year for the four cameras I had. As I became more and more aware of privacy issues with cloud video, I decided enough was enough. I took down the Nest Outdoor and replaced with a Ubiquity G3 bullet. I added three more of them over time. All my video is now stored on a local server and offers almost instant when I’m at home. Access when I’m away from home is also pretty snappy.

Smart light bulbs.

I tried a pair of Ikea Smart Downlighters in my downstairs loo. They were easy to install and use, but light switch muscle memory proved too strong and I had to take them out. I ended up using an Aqara switch in their place and that worked an absolute treat!

Den Light Switches

I bought into Den Automation’s crowd funding via Seedrs and preordered a few hundred pound’s worth of their stuff. After lots of delays in manufacturing, it eventually arrived. I’ve written about the installation and my first impressions of the kit. It worked pretty well, but after a few months the company went into administration and their cloud was switched off. Thankfully I’d figured out a way to make it work with MQTT so I was able to use them for a while longer. Some of the units eventually lost connection and couldn’t be re-paired without the cloud. They did eventually restore the cloud, but I’d lost interest at that point.

An expensive lesson in the perils of both early adopter hardware and investing in startups.

Get somebody useless to wire my alarm.

This isn’t really a technology issue, rather a human issue. I added a Konnected board to my wired alarm and made some shocking discoveries.

What will I do again?

Home Assistant

I’ve had a Home Assistant installation in my previous home for more than a year. The MQTT and Zigbee services ran on the same small tower. I was also using NodeRED for some more advanced workflows. I found it very stable and it never once failed, not in all the time I had it installed.

Smart lighting with the Shelly1

The Shelly1 relays I installed were absolutely fantastic. I could not recommend them enough. Installing them requires some knowledge of wiring, but I had no issues installing them into several of the lights in my house. The pendant housing was the only real problem, so this time around I’ll have to find something a little larger.

I’ll also make the electrician aware at the beginning that I’m planning on installing them and ensure that the wiring is suitable. There will be a few places (outdoor lighting) where there won’t be a ceiling rose, so we’ll have to figure something out for those.

I also plan on installing some of their Dimmer models, so we can have some mood lighting and potentially enable low level lighting at night, for the kid’s nocturnal trips to the loo etc.

Smart Thermostat

As noted above, I was not planning on a Nest Thermostat. This time I’ll be installing a Tado system. It’s completely wireless, with the control unit operating off batteries, which means we’ve more flexibility in choosing where we install it. The company also make smart TRVs, which can be operated remotely. Best of all, I think, is that individual TRVs can turn the boiler on, rather than relying on one central thermostat, we essentially get a zone per room.

It also has an API, integrates with Home Assistant and works with HomeKit too. Offers lots of flexibility. The advanced features require a monthly subscription, but I feel happier paying £30 a year than using the Nest.

Install an alarm

Rather than going for a wired alarm this time around, I’ve decided to go for a wireless model. I wanted flexibility and smart home integration. Some wired alarms offer this, but the newer generation are far more integrated and connected. I’ve settled for the Abode alarm, down to its broad compatibility and Homekit support.

Smart Hot Water

In my last house I had an unvented cylinder for storing hot water. Pretty standard.

One of the major pains we experienced was running out of hot water. This happened on and off, usually when we wanted to draw a bath for kids. I improvised a way to measure the temperature in the tank using some probes and this sort of solved the problem. Assume we checked, we learned that particular temperatures across the tank gave a rough indication as to whether we had enough water or not.

Whilst watching the great Fully Charged on YouTube, I happened across one show about the Mixergy hot water tank. I was really impressed and when the purchase of the house went through, I ordered one.

The idea is that the tank can maintain a certain amount of hot water in the tank, rather than having to heat the entire tank. You can schedule it during the day, heating enough for showers in the morning and than maintaining some for use during the day. It’s about 50% more expensive than a standard tank of the same size. I’ve opted for one that can support Solar PV, so in the future I hope I can heat the water with some solar panels. If I get a smart meter installed, I hope I can also use cheaper electricity at night to heat the water, rather than just relying on gas.

Progress updates

Once the work has begun, I’ll post a few updates as I go.

Installing Konnected Alarm

Back in February of this 2020 (This post has taken me a year to write!), I preordered an alarm panel from Konnected.io.

The idea with the Konnected alarm panel is that you can take your existing wired alarm and connect it to your smart home setup. It’s a very clever bit of kit, which I came across accidentally.

It took a little longer to arrive as I there were some delays in the manufacturing process, but a little box was delivered containing a power supply, some cables and two boards; the alarm panel and the interface board.

Interface board (left) and alarm panel (right)

Current Alarm

To see what I was dealing with, I opened my alarm panel after entering the engineer’s code.

My panel. Nothing labelled.

I was hoping to see something labelled, which was let me know what wires connected to what sensors. I knew how many door and motion sensors I had and that lined up to the number of zones being used. Unfortunately, I had no idea what was connected to what.

After reading the manual, I discovered that tamper detection was disabled.

Using my multimeter I had my wife go around the house, triggering the motion sensors. Oddly, some of them didn’t seem to have any effect. They were getting power as the lights turned on, but no voltage change was registered at the panel. To help me understand what was going on, I opened one of them up.

The fucking sensor circuit wasn’t even connected. HOLY FUCK. I mean HOLY HOLY FUCK. I connected that one and the panel showed the voltage change as expected.

Sensor circuit shorted with resistor, which would normally be okay if using tamper detection

Opened another sensor to find the circuit shorted with a resistor. Normally this is fine when using resistance based tamper detection, but my panel wasn’t configured for this.

I double checked the Zones configured and found that two of them weren’t even used. A few clicks here and there and that was rectified. A walkthrough confirmed all the zones were wired up and responding.

Not only were some of them not wired up, others weren’t even included in the panel.

I had to go outside at this stage because my language wasn’t suitable for the ears of children.

After putting everything right, I proceeded to actually connecting the Konnected Alarm Panel.

Installing the Konnected Interface Panel

After calming down and having labeled the various zones, I started installing the Konnected Interface Panel.

Pulling in the interface cable
Inserting the reference voltage wires into the panel
Adding the zones

Thankfully, this step was pretty straight forward and didn’t take very long. It was a case of adjusting the little resistors until the red light went off. When the circuit was triggered, the light would turn on.

The Alarm Panel itself. I left this outside the panel so it had a good WiFi connection

Setting up Home Assistant

I use Home Assistant for most of my Smart Home stuff and Konnected was fully supported with its own Integration.

Once I had connected the Panel to the WiFi using the iPhone App, the Home Assistant setup pretty much took care of itself.

You indicate which zones are used and what they are
The sensors configured on my dashboard

Summary

The Konnected hardware is really solid and was really easy to setup. As I understand it, they are a very small company, but what they’ve done here is really clever. Setup was faultless and it’s never gone wrong.

One of the most interesting uses of this product is that it can enable remote arming/disarming of your alarm (if the panel supports it). I never got around to doing this, but the idea is simple. You install a small relay, connected to the Konnected panel. By turning on and off the relay, you can use the Key Switch feature of a standard alarm panel to arm/disarm it. Home Assistant supports this via it’s Alarm extension, but I think it would only really work if this could be used in tandem with the existing keyboard panel. It’s possible to have your panel emit high voltage via one of the Zones, but as all the zones on my panel are full, I couldn’t try this out.

If you have a wired alarm and you’re looking to make it smart, I’d highly recommend this product.