Installing a tado Smart Thermostat - easy yet difficult - looking positive and already helping

Great narrative @EverythingNeedsAUserName 

Frankly I think this Forum can do better at support than any chat-bot or manual. Let’s see what help we can put together between us.

I’m going to kick off by suggesting multi-core mains control cables (class YY) which can link the boiler to the Tado receiver:

7-core YY mains cable at £1.56/mtr +VAT and 5-core heat-resistant at 64p/mtr +VAT from TLC-Direct

With YY control-cable you get an earth and all the other cores are black. Label them with PVC tape as you proceed. YY-cable may only be used for control signals. It is not certified to carry power to an appliance even tho’ it’s mains-rated.

Screwfix also do a 10m coil of cable type 3095Y (5-core) at £7.52 incl VAT. This has coloured cores. The equivalent from Toolstation costs £8.87. Cable type 3095Y is mains-rated and heat-resistant. It’s normally used for temperature controls close to hot-water cylinders.

If you’re trying to fit a Tado receiver in a position where there was a originally space for a 2-gang control box, I suggest you get a PVC blanking plate. Bolt the Tado receiver to it in the centre, leaving the two screwholes at the ends for the M3.5 bolts to secure onto the existing patrass-box.

PVC faceplates are thin and can be drilled without shattering. Toolstation have them for 59p each. But ignore their photo. It actually looks likes this:

If you don’t feel able to bolt the Tado receiver to the blanking plate, double-sided tape would probably suffice. Either way the receiver will cover up whatever size hole you’ve made for the cable to pass through.

Three cables feeding into a central-heating control point is quite common @Tim_OVO.

There is one to supply the electricity needed by the thermostat/time-clock itself.

The second cable connects back to the boiler with a ‘switched live’, telling it when to operate.

Cable number three goes to the 3-port valve which directs boiler output either to radiators or a DHW cylinder. That’s usually a 3-wire plus earth cable, but can be 4- or-5-wire if the controller receives feedback from the motorised valve.

Moreover, if the house had been through a couple of previous boiler or time-clock replacements in its time, then those cables could be a rich assortment of wiring colours!

A ‘black’ wire could be a neutral or a live control-signal to the 3-port valve.

And at this point you begin to realise that a cut-price offer on a wonderful new ‘wireless’ smart thermostat might result in some considerable time being spent by a qualified electrician or heating-engineer to install the receiver end. All this costs money.

Here’s an example of a YY Control-cable connecting to a box on my own Thermal-store. It’s got 5 internal wires, including two blacks. I’ve labelled it so you can see what each does:

This is definitely the ‘right’ way to connect this box to the manifold control unit on the next floor-level. But many installers wouldn’t carry such an exotic cable.

Instead they’ll use the common mains cables for lighting circuits (1.5mm²) and label the conductors at each end (hopefully!).

If a cable doesn’t have enough cores, they’ll simply run another cable alongside it.

Well I didn’t expect that response from @PeterR1947 

Where’s all the warnings about using a qualified electrician and not trying to replace mains thermostats yourself?

Thanks @Transparent 

I’m not going to add any additional wires to move it further away, as it works as-is, and that’s just more connectors to try and squeeze into a small space.  I was waiting till I could get to the electrical wholesaler to get a blanking plate - and wall box.  I only had single ones in my electrical stores.  It is amazing how much you can collect over 45 years and still not have what you are looking for.

As you said, it wasn’t surprising to find that many cables linked up together.  I WAS surprised to see the tado drawing suggesting it would be a single cable.  That has never been my experience, and I don’t know how it ever could be.

Part of the reason I stuck with the tado help was because I planned to create this post.  I thought I needed to experience the full process.  I just didn’t expect it to be so long winded and useless.

With that in mind, I chased up the unanswered email about the incorrect wiring diagram for the thermostat. I was told that they’d answered a similar question from me about the receiver so didn’t think it needed answering!  Astounding, as that first answer said to connect the earth wire to the earth terminal on the receiver (as I’d told them I was doing). But the tado thermostat is wireless, so doesn’t have any terminals - so their first reply can’t have been applicable.  I hope they fix their diagrams.

So far the tado is working. The absolute requirement for siting 30cm away seems to have been unnecessary.

INITIAL THOUGHTS ON OPERATION after 4 days

• The ease of setting differing times and temperatures compared to the previous system is wonderful.  Rather than being too hot getting up, we’re set for 18° briefly, then (for now) 14° during the day on the basis that unless it gets really cold, it won’t kick in; then 20° for the evening. 
• We’ve only used the AWAY setting on the very first night.
• It is now easy to see how the house cools down overnight and daytime, but perhaps not as much as I’d thought.  I now wish I’d had this before we got the cavity wall insulation filled back up, so I could see whether it made a difference.
• The “Early Start” setting is clearly operating.  It fires up the heating up to an hour beforehand.  
• We’ve already experienced the “Open Window Detection” - except that it was the front door.
• The app gives MORE information than the web site!  But it isn’t as easy to read. I’ve not found a way of getting any data out - just graphs.  The data appears to refresh every minute - you can press and hold your smartphone screen and move across to see the precise information at any one time.

Web site	App
	Climate Report icon top right
The following screenshots are only in the app (to get some of these, I’m using “YourPhone” in Windows 10 because on the phone itself, it kept overlaying the navigation bar).
This shows when the heating was on; the grey shading shows how hard tado was asking for heat.  I’m not aware of that facility in the boiler itself, which I think is just ON or OFF.  Note how it overshoots the target, apparently designed so that it doesn’t need to turn the boiler on and off too frequently. The scheduled evening temperature is set for 17:00; to achieve that, tado started to call for heat at 15:59, a full hour in advance.  It hit desired temperature at 17:08.  Before we got the tado, I actually had the old controller set to switch on at 16:00, so it is doing much the same.
The peak was 20.8° and the evening low was 19.8°. You can see how it started to call for heat again - that was at exactly 20°.

@Tim_OVO in my first post I realise that I missed the images that showed how to label my specific controller. I'd intended to do so to show how the instructions in the app are designed for your own specific devices. 

I don't seem able to edit, nor can I send you a PM that includes images. Please could you add an extra row in the table as shown, and add these?

The warning to "Make sure you label the stickers exactly as shown..." , combined with the image on the first line not to proceed if they differ could panic a lot of self-installers. 

Such a great guide to installing a Tado yourself and the great to hear you’re already seeing the benefit, @EverythingNeedsAUserName.

I’ve made the requested edit to your original post (hope I got that right). As @Blastoise186 hints, more posts like this and you could be well on the way to earning yourself some extra special super-user powers!

Keep us updated on how you get on with the new smart thermostat! 

I appreciate that air source heat pumps work very differently and have to be operated very differently for optimum performance, operate at different temperatures etc. 

Having said that, i would have thought the Tado output data for a gas boiler setup would be a useful background input when the time comes to potentially change to an air source heat pump setup  or something else. Having some actual data on temperature loss to compare with air source heat pump calculations would be interesting if nothing else i would have thought? Be curious to know what posters more experienced about these things than me think.

I ask as it is one of the reasons i have thought about getting one. 

@Jess_OVO beautiful edit, thanks. Couldn't have done it better ;)

@Tim_OVO Three initial thoughts on benefits. (I got trapped in putting down features, but I think I've fixed it) :-

1. A more comfortable house in line with our lifestyle. Through feature: Set multiple different temperature blocks in any one day and different from day to day.
2. Save money. Feature :use the app to turn the heating down or up or off or on while away from home.
3. Save time and remembering. Feature : set lower morning temperature. Previously I'd try to remember to lower the thermostat as I went to bed, otherwise it could feel too hot in the morning. Then I had to turn it up again in advance of the evening.
4. DRAWBACK :Costing money and time! I've less time for my family history research. My subscriptions are not being used. 

The OVO insights will be available in a month. The algorithm needs data. The tile in the app is merely a link to the "tado/my-thermostat/<month>" web page in my ovo account. 

Thanks for the badge. I'm glowing with pride.

@Jeffus it was a one-off cost, no subscription for what I have. They do have an extra monthly subscription for "Care & and Protect" which offers a monitoring service. It seems to watch your boiler and warn you about unusual patterns.   I've initially dismissed it as unnecessary. I guess they'll also hope for more sales of different or improved devices. 

tado help desk. I got an email reply about the thermostat wires. It is very clear that English is not their first language. They're a German company. I was told to do what I'd asked them to confirm I'd already done - as if I'd never said anything. 

Hi @Jess_OVO No, the main reason for joining the trial was because the gas boiler was on its last legs being over 20 years old (and I also needed to move it to make space for a kitchen renovation!)

The Nest is happily doing its own thing and turns the ASHP on at around 5am at the moment, depending on the weather, to heat the house for 7am. Mine is a high temperature heat pump so can respond quicker than other low temperature ASHPs (although I’m trying to run it at a fairly low temperature for efficiency).

Unexpected information from the tado! 

On Friday morning I thought I'd have a quick look to see how close we'd got to the heating coming on. 

My big surprise was to find that when the water heating had been triggered at 4am, the tado recorded a half degree temperature rise! (4am.is to use cheaper electricity, and be ready for morning shower but not leave a full tank at its highest temperature for too long so it loses all the heat).

The hot water pipes from the boiler run through the ceiling /floor space between the two floors of the house, which is above the tado thermostat. 

We've had the diverter valve replaced twice already because even in summer it was sending water round the radiators instead of to the hot water tank. It might be failing again.

This morning (and in the week since installing the tado) the hot water had no impact on the house temperature. 

This is now something to watch out for, and get the plumber back if it happens again. 

BTW, this morning the tado instructed the central heating boiler to provide 1/3 heat. Overnight external temperature was 12`°. The radiators became off-cold, but not warm. 

Also the house warmed up without heating yesterday day-time. Not bad considering that our windows are east/west, and we have another house south which blocks the midday sun from the side wall. 

@Tim_OVO if we leave the water until nearer 7 am to come on, it wakes us up!

The tado still gets the information about the hot water in the old-fashioned way, by a wired signal from the old thermostat clamped to the side of the hot water cylinder. That only gives a signal when the water reaches the desired temperature. No smarts involved. 

The heating of the hot water should have no impact whatsoever on the heating of the house.(*)

The fact that it did on that one day suggests that there is an incipient problem with the diverter valve, something that we have had in the past.(**) 

The tado smart thermostat has taken over the former functions of both thermostat and boiler controller. It controls the boiler, and whether its output goes to radiators, hot water cylinder or both. Rather than have to stretch into a dark corner to program it, we can do so on a smartphone or on a web browser.

(*) There is a minuscule underfloor heating effect in the bedroom due to the uninsulated pipe run from the boiler to the valve. 

(**) 15 months ago we were woken up by the radiators being full on despite the heating being set to off. We ran out of hot water, and called the plumber who replaced the valve. 5 months later it failed again. 

 how a Diverter valve operates. Heating /both /water. On ours the switch is electronic not manual. You can hear a small motor doing the turning. 

I hadn't looked specifically for features. I wanted to dip my toe in the smart home arena, and OVO had the offer on tado. That also links through with my OVO account.