DIY Doctor

Adding smart lighting switch to existing setup

Postby Therealwiggler » Sun Aug 02, 2020 7:41 am


I think I already know the answer (and it’s probably no) but I wanted to post on the off chance I was wrong.

We have a light switch in every floor in our house (three) to control all the lights in the hallways - totally off 4 lights.

Today I took the light switch off the front of one of them to have a look and I can see that I have 2 red cables, 1 yellow, Earth and a blue and black cable.


Before I call my electrician is there a smart switch available that can deal with this type of setup?
Rank: Labourer
Progress to next rank:
Posts: 2
Joined: Sat Aug 01, 2020 10:52 pm


Simply Build It

Postby Mr White » Sun Aug 02, 2020 9:24 pm

I would suggest you ask your electrician, that way he will know what he is going to install.
Mr White
Rank: Site Agent
Progress to next rank:
Posts: 912
Joined: Tue Jun 20, 2017 9:54 pm

Postby Therealwiggler » Sun Aug 02, 2020 9:31 pm

Thanks for the reply. Unfortunately my electrician won’t touch smart switches - writes them off before even looking at the possibilities so was after some advice. I suppose I best find myself another electrician
Rank: Labourer
Progress to next rank:
Posts: 2
Joined: Sat Aug 01, 2020 10:52 pm

Postby ericmark » Mon Aug 03, 2020 8:50 am

I think so, but not sure, with most electronic switches with no neutral to have two way switching you have a master and a slave, uses the same wires as a mechanical two way switching arrangement, but uses them in a different way, so you have an S wire instead of a com wire.

I know with some dimmer switches you can use two slaves with one master, but not sure about on/off switches, so Energenie MIHO043 is a pair of smart switches which do not need a neutral. (£35) but you would need to ring Energenie to see if you can use two slaves with one master.

Be aware the remote controls cost £11 each you can have up to three, and the hub £70 so not cheap. Also bulbs must be over 5 watt each I have found.

There are other makes, Lightwave for example, but not personally used them. If you have G9 bulbs forget using neutral less smart switches, finding G9 bulbs which don't flicker is a nightmare, did find some in the end, but so large the covers will not fit on the lights, and one failed within 24 hours.

With the standard BA22d bulbs no problems, some GU10 bulbs flicker I swapped them for other bulbs in the house.

You will need new back boxes as the switches are deep, with no screw connectors top and bottom. I used spacers.

Where a neutral is available the type using a neutral are cheaper and better in the main, so as Mr White says talk to your electrician. I fitted 5 switches, and then removed 2, the upstairs switches have worked well although one needed a load capacitor fitting. But down stairs been more trouble than worth it, random turning off.

My son says his Alexa works well, not sure he would admit if it didn't, but my Nest Mini is like a mischievous little boy, however it did tell me how to spell mischievous, I would say hay google turn off to stop music, but it would reply turning off 5 switches and turn off lights, and when asked to turn lights on, would reply "I don't know how to do that yet".

Some of the smart devices have worked well, others have been a flop, we like the Nest Mini, but don't trust them with heating or lights. We were told Energenie MiHome was designed to work with the Nest Gen 3 thermostat, in a way they do, but not in a way one can use, so the TRV heads are independent to wall thermostat, I say this because it is the same hub which works the TRV heads, light switches, sockets, and energy monitors.

I am sure I could use IFTTT to further automate what I have, I have a Mihome Smart Plug + connected to my Lidi AC, and as long as I have turned AC off using the Smart Plug I can turn it on with my phone, and also see the room temperature from the two TRV heads, and see if the AC is simply blowing air or cooling, and I will set it up on hot days so I can turn it on before I get home, but although in winter I can set room temperatures from my phone and set up geofencing so it auto turns up room temperatures with the TRV heads, I don't use it. The main wall thermostat turns off whole boiler when I leave (Nest Gen 3) so no need to control the TRV.

I also have cheap blue tooth eQ-3 heads also programmable which in many ways do a better job to the Energenie.

OK you only asked about lights, but they all interact with each other, so you need to consider what you want in the future, I started because I wanted to turn off an exit alarm when my mothers carers were due to arrive. And it expanded from there.

The most complex bit is central heating, well not so much since I have moved as now using oil, but with gas and modulating boiler no system seems perfect so some where there is a compromise, it depends if the boiler is opentherm and if house is already split into zones, only opentherm thermostat which will work with zones is EPH which does not support connection to TRV's. Honeywell EvoHome is one of the better, and the price reflects that, most also do light switches and other functions, and often will not work with other makes.

So once you make that first step, your locked into some ones system, so you can't select in isolation.

From reports it seems Lightwave is one of the better systems, but clearly because your locked into some ones system no one fits two different systems so no one can compare them.
Rank: Project Manager
Posts: 2559
Joined: Fri Oct 02, 2009 8:49 pm
Location: Llanfair Caereinion, Mid Wales.

Display posts from previous
Sort by
Order by

  • DIY How to Project Guides
  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!

  • Related Topics