Extending a Multi Zone System

JohnPerriam

I have installed a Tado system in my home and would like to extend my system. 

My current set up is :-

A three zone system with one valve controlling the hot water

A second valve controls the downstairs central heating

A third valve controls the upper floor central heating.

The down stairs central heating system has a wireless thermostat and 6 smart TRV radiator thermostats allowing independent control of almost all radiators downstairs. In addition to that we have an internet bridge that is connected to the home router via a TP Link powerline network extender. In the utility next to the boiler we have a Tado Wireless receiver (programmer).

Upstairs the heating is controlled by a single wired Tado thermostat. This thermostat activates the control valve and heats all radiators upstairs.

I am thinking that we could improve the system by adding another set of smart TRV radiator thermostats upstairs. I would like to control 5 radiators upstairs and still maintain the two zone status.   However, I do not see how the system would know how to select only the upstairs control valve.

Can you please advise if it is possible to control individual radiators upstairs (within their own zone)?

If it is possible to control individual radiators upstairs can you please recommend the additional equipment we would need?

Thanks

johnnyp78

Sounds like all you need is the additional trvs. Depending on how your system’s been setup you may need to create additional rooms on the app and give them the right zone controller (the wired thermostat).

limeyard

Hi John,

I am presuming that the wired thermostat on the first floor is either in the principal bedroom or on a landing. First rule: Do not fit any sSTRVs in the same space (room) as the wired thermostat. STRVs fitted elsewhere can be set as independent or associated with any wired thermostat (zone). In your case, you would obviously associate it with the first floor stat to ensure that when it called for heat, the zone valve would be opened.

If you already have compatible normal passive (wax) TRVs installed, you just need to swap the heads for your new Tado ones.

After installing and pairing an STRV, to make the settings, (independent or otherwise) go to Settings >> Rooms and Devices.

johnnyp78

@limeyard I’m afraid you’re wrong on the first rule. There’s no reason not to put a tado trv and smart thermostat in the same room - they work together so it’s not an issue. I agree with the last two pars though.

JohnPerriam

Thanks for the replies.

@Limeyard, I was not sure that we could associate a zone to the wired thermostat, but your reply answers this question.

@JohnnyP78 The wired thermostat is on the upper floor landing and will not be close to a sTRV.

Thanks again

John

johnnyp78

Your wired thermostat will already be a zone controller - it’s what’s telling the zone valve to open, unless I’m misreading something. All you need to do is make sure the tado rooms in that zone have it as their zone controller.

limeyard

@johnnyp78, [Quote} "All you need to do is make sure the tado rooms in that zone have it as their zone controller."

That's right, a wired thermostat controls a zone - it is a zone controller - and if you want to be sure that the radiator gets heat, you have to assign the zone stat as the zone controller in the app - so that the zone valve gets opened when the STRV calls for heat. (Or you can choose to assign independence.) As I said.

Choosing independence would relegate the STRV to a role as a programmable 'limiter'.

You can, of course, break the rule, but why would you do that? The two stats would then be fighting for control of the same space.

@JohnPerriam, Out of curiosity, do you have any rads in the space where the wired thermostat lives? If not, that gives you maximum freedom of use of the other rads STRVs in that zone. That's an interesting idea! 😉

johnnyp78

No, the stats don’t fight for control, that was the point I was making. In Tado one device per room is set as the measuring device. If there’s a smart thermostat available it’s usually that due to better accuracy, though this might not work in the OP’s case due to the thermostat’s fixed location.

limeyard

@johnnyp78, Tado doesn't know where your devices are until you provide the info. The wired thermostat is by definition the zone controller. Unless you assign a STRV to a zone, Tado doesn't know where it is, so cannot open the zone valve when the STRV calls for heat.

If there is an STRV in the same space as a wired thermostat, and the STRV is assigned, and they are both calling, the higher setting will always prevail, but why would you put two thermostats in the same space?

I am sure that @JohnPerriam will see how it works when he comes to open his app during installation.

limeyard

The above is not quite right - I'll clarify when I get back.

johnnyp78

You would put a smart thermostat in the same room as a Tado trv if the tado trv is covered by furniture for example, or if you have two Tado trvs in the same room giving different readings. Not sure what you mean by ‘the highest setting will always prevail’ - you set one device per room as the measuring device. That isn’t the same as setting the zone controller, which would would always remain the device connected to the boiler or zone valve.

JohnPerriam

Hi Gents (@limeyard and @johnnyP78)

Many thanks for the information.

My wired thermostat is located in the upstairs hall. There will be no sTRVs in the Hall. However the bedrooms coming off the Hall will all have sTRVs at some point in the near future.

You have both been very helpful and I now know that if I designate the wired thermostat as the upper floor zone controller I will open the upper floor valve and feed hot water to the open TRVs. This is all the information I need and I have ordered the sTRVs from Amazon this morning.

Thanks again for your help.

Regards John

limeyard

Glad to have been of help @JohnPerriam. I am sure that it will go well, but if any further clarification is needed, one of us will have the answer.

Remember that you need a compatible existing TRV in place so that you can swap the head. One of mine was not compatible but I was able to get a cheap one from Screwfix: https://www.screwfix.com/p/white-angled-thermostatic-trv-15mm-x-1-2-/60368 which did the job just fine.

If you need to do this, I am guessing that you will know how to change the valve without getting too wet.

JohnPerriam

Hi JohnnyP78 and Limeyard,

I have purchased the sTRVs(5 of them) and started to fit them to the radiators.

However I was not able to associate them to the wired thermostat. In the app the wired thermostat is simply shown as a lone device. Do I have to change dip switches to turn it into device that sTRV can associate with?

Thanks and Regards

John

johnnyp78

I think you need to do a bit of reading on how Tado works - the wired thermostat needs to be set as the zone controller for the rooms. There aren’t any dip switches on Tado products.

https://support.tado.com/en/articles/4689126-how-does-tado-control-heating-zones-how-can-i-change-the-zone-controller-of-a-room

limeyard

@johnnyp78, what wireless thermostat? @JohnPerriam didn't say anything about a wireless thermostat, did he?

Your link is a good one - you probably ought to read it.

@JohnPerriam, [quote] the wired thermostat is simply shown as a lone device. [/quote]

Is it greyed out? If not, you should be able to click/tap on it to set it as the associated device.

This is what mine looks like (on the PC): Clicking on the 'Zone Controller' panel at the bottom of the first image opens the second image which enables you to choose your preferred option. I am guessing that you will just have two choices - the wired thermostat (which is a zone controller) or 'No Zone Controller (independent)'.

Let us know how you get on. I'm sure I'm not the only one who will want to know. 😉

johnnyp78

Sorry, that should of course read wired thermostat. Thanks for pointing it out, I’m glad we agree that the link is a good one.

JohnPerriam

Hi Gents,

Thanks for all your comments. I appreciate the time you have both given me.

We currently have only one zone showing in the app:-

The BP 1806259456 is our wireless receiver situated in the utility room. This controls the hot water and downstairs heating.

The upstairs wired thermostat is set as independent and this operates zone two in our existing system, however this configuration does not give us the ability to set the wired thermostat as a separate zone controller which we now need if we are to add individual sTRVs upstairs.

I probably did not make it clear in my initial description that I am extending the existing system that has been working very well for about eight months.

I show below this setup in the app (from my PC).

I hope this explains the situation better.

Regards

John

johnnyp78

I think if it’s not an option you need to get tado support to enable the wired thermostat as a zone controller. You could try reinstalling it but might be better to talk to Tado support first.

limeyard

I am getting a bit confused now. I am assuming that the pipework that supplies heat to the upstairs radiators is controlled by a two-port zone valve and the wired thermostat on the landing switches (controls) that valve. If the upstairs measuring device RU3807398656 is the wired thermostat - which you appear to have set as Not assigned - then it needs to be set as the Zone Controller.

When you add an sTRV in the app - Principal Bedroom, say - you should get the option to set its Zone Controller as RU3807398656.

I have just looked at my own system to try to understand how you have a wired thermostat unassigned. When I tried to change the assignment on one of my wired thermostats, I got a message telling me that the only way it was possible would be to set it up as a wireless thermostat. Is that what you have done? If so, you need to go back and undo that. I expect that everything will then fall into place.

I hope this helps.

JohnPerriam

Hi @Limeyard & @JohnnyP78,

You are right we have 3 two port valves, one controls the hot water, one the downstairs central heating and the third controls the upstairs central heating which is operated via the upstairs wired thermostat.

Yes we get an option to set the wireless receiver BP1806259456 as the zone but that only operates the downstairs heating valve.

One thing I noticed from your screen is that all your zones were controlled by wired / wireless thermostats not the main wireless controller. Our system only shows the main wireless receiver as the zone controller not the downstairs wireless thermostat.

We just cannot find an option to set the upstairs wired thermostat as a zone controller.

Is this the possible issue we are having with our system?

We will be talking to Tado shortly.

Thanks Again Regards

John

JohnPerriam

Hi @Limeyard and JohnnyP78,

Just fixed it.

I now have the upstairs wired thermostat on the system and have fitted 3 sTRVs to the upstairs radiators.

Tell you more later.

Regards

John

HarveyB

John,

You said that you would get back to tell us more about how you fixed the zone problem on your system.

I have encountered the same problem adding a Wireless Stat/receiver and TVRs to an existing wired stat/TVR installation.

When I added the receiver it created its own zone and removed the Wired Stat zone. Reinstalling the wired stat still didn’t sort it.

I had an exchange with Tado support. They stated that it is not possible to have zones on wired stats when a wireless receiver is present.

Please can you (or anybody else) give any insight into how you solved this?

FOR INFO:

I ended up connecting upstairs and downstairs valves in parallel. Not a big problem as all rads now have Tado TVRs anyway.

I now have a redundant wired stat but would have preferred two separate zones.

JohnPerriam

Hi Harvey,

I did solve the problem with Tado's help.

They allowed me to connect the upstairs TRVs to the upstairs wired thermostat. Apparently only by contacting Tado can you get the wired thermostat added as a device that is able to communicate with TRVs.

So I could associate all upstairs TRVs to the upstairs wired thermostat. I still have a wireless receiver in the system. However the wired thermostat (upstairs control) does not have any communication with the wireless receiver. My wired thermostat is directly connected to the wiring centre so there is no indication of what is happening upstairs on the wireless receiver.

I now have a system that is totally independent both upstairs and downstairs.

I hope this helps.

I can send a wiring diagram of the system if I have not clearly explained how the system works.

Regards

John

HarveyB

Thanks John,

So effectively the wireless stat and receiver control the downstairs circuit (diverter valve), associated TRVs and Hot Water.

the wired stat controls the upstairs circuit(diverter valve) and associated TRVs.

I understand your point about the wireless stat/receiver not talking to the wired stat. But thats what I would expect.

Just as when one uses two wired stats to control zones, they would also be totally independant.

The zone/diverter valves trigger the boiler not the stats.

I now just need to decide whether to pursuit this option with Tado. I assume I would need them again if I had to replace one of the components.

As it stands I currently achieve the same by associating all TVRs with the “receiver” and open both diverter valves together. Same result as all rads have Tado TVRs. It’s just not a “clean” as separate zones.

Bit of a dilemma really.

But thank you very much for your help.

Harvey

hugbilly

@JohnPerriam I would be interested in seeing your wiring diagram if you felt like posting it, and I think it might help the many forum users who have questions about adapting their zoned heating systems to tadoº

HarveyB

Here is a schematic of my setup

I hope it helps.

Tado Control - Wireless Thermostat.pdf

JohnPerriam

Hi Gents,

Please find attached my wiring diagram.

The note about the setting of the wireless controller is important.

Regards

John

Tado Wiring Diagram.pdf