Boiler has to be on constant ? Polypipe and central heating

Caz217

Hello,
I've just installed tado in our home after a lot of back and forth with customer support ensuring it was all compatible.

***System in home***
Boiler - Worcester Bosch greenstar highflow 550cdi.

Downstairs - polypipe underfloor zoned heating, with individual thermostats.

Upstairs - radiators with 1 centre wireless thermostat. 1 bypass radiator on the landing, all other rooms TRVs.

***Kit purchased***

With the help of tado I purchased 1 V3 starter kit.

4 additional wired smart thermostats.

5 TRVs.

***Tado installed***

The down stairs has polypipe underfloor heating. This is zoned to each room and has a wired thermostat in each room. 4 wired tado smart thermostats have replaced the polypipe thermostats.

Upstairs all rooms and landing are heated by radiators. There was one wireless thermostat on the landing, which was centre. Behind this thermostat was the wiring for a wired thermostat. A tado smart thermostat has now been wired in.

On the landing there is also a radiator. This does not have thermostatic valves as it is the 'bypass radiator'.

All bedrooms and bathroom have been replaced with tado smart TRVs.

The system was installed with ease, so I thought. The internet bridge connected up no problem and all tado items synced and we're set up fine.

The smart thermostats appear to be functioning as you hear a click in them if rank the temp up or down. However during the install it clearly says your boiler must be on constant.

I thought ok, it's on constant but tado will tell it turn on and off with the smart thermostats and TRVs.

The TRVs appear to be working great, radiators Will only start heating the room if it drops below the desired temp.

But my landing is at a constant 23 degrees due to the bypass radiator always being on, despite my landing thermostat only being set to 19.

The downstairs underfloor heating I suspect is also always on constant as my living room is stifling, at around 22 degrees constantly despite only being set at 19 again.

I've this morning turned out Worcester Bosch greenstar highflow 550cdi to auto and have attempted to rank up a room radiator upstairs to see if the boiler fired up, It did not.

Surely having my boiler on constant is not efficient and will be costing me a fortune. How do I get my tado heating system to speak to my boiler ?! Have I missed a bit of kit ?

Any help would be appreciated 👍

Mickyman

I do not have your type of boiler. But how I understand it, is your boiler is switched on all the time . So if you have a timer on your boiler, set it to on all the time. Then the tado receiver will turn the boiler on and off when it needs to as set by your Tado room settings.

Caz217

That is what we have done, placed the boiler constantly on, however it is not turning off when the landing wired thermostat reaches temperature and I suspect it is not turning off the underfloor heating. Meaning it is constantly running despite being over the desired temperature.

MrTado

Hi,

I had a similar set up a few years ago, however I did not need to leave my boiler on the entire time to make it work.

I don’t know if you need to let Tado know that you have under floor heating, I don't have it in my current home, but in my previous property Tado needed to be aware.

Rather than trying to ask more questions, I’ll explain how my system worked.

Prior to the Tado install, I had 3 downstairs underfloor heating zones, each zone had its own controller and each controller acted for that zone only. If I manually used the controller for the kitchen, then only the underfloor heating came on in the kitchen. Each controller had a timer clock that would call for heat at pre set times, subject to the zone being colder than the required temperate. Hope this all makes sense so far….

In terms of upstairs we had a single thermostat and radiators in each room, plus the bypass radiator that you refer to. Each radiator had a manual TRV attached to it. The upstairs thermostat was attached to the digital central heating controller (timer clock) along with the hot water - and this controller was used to set the times that the heating turned on upstairs, but would only trigger / call for heat from the boiler if the temperature was below the set temp on the upstairs thermostat at the times it had been programmed to be on. Hot water came on at the pre set times only.

When we installed Tado, it was set up as follows:

• each zone controller for the underfloor heating was replaced with a Tado wired smart thermostat. We could manually increased or decrease the room temperate at the smart thermostat - that would generate the ‘click’ noise that you mention and call for heat, or if the zone was on and it was too warm stop the call for heat.
• additionally we used the Tado app to set up the times that we wanted the underfloor heating zones on in each room and the ideal temperature. We could still manually override this by increasing / decreasing the temp at the smart thermostat or by using the app.
• because these zones are wired, they directly tell the boiler to switch on / off as needed

upstairs is slightly different

• as part of the set up, the digital central heating controller (timer clock) was replaced. Ours had 1 central heating channel and one hot water channel. Tado used to have a device called an Extension Kit which was used for this purpose, it replaced the heating controller / timer clock, they don’t make this anymore, but I believe that the Add on Wireless receiver does the same thing. I don’t think that you have this however from your description.
• the manual thermostat control was replaced with the wired Tado smart thermostat
• the individual radiators (apart from the bypass one) were fitted with the Tado smart radiators thermostats - and set up as individual rooms on the Tado app.
• by using this, we were able to use the Tado app to pre programme the times that the hot water turned on and additionally pre programme the times that the upstairs heating would turn on at radiator level

I think where your system is different is the fact that you have been told to keep the system on - which is a similar set up to what I currently have. In my new home we have a single wired smart thermostat upstairs and each room had a Tado TRV. We can turn on each radiator independently, and each one is set up as its own room on the Tado app, however it does not mean that the boiler is running 24/7, it only comes on when the smart thermostats / tado smart radiator thermostats call for heat - because the heating controller / timer clock will only call for heat if 2 things are true, the clock on the heating controller / timer clock is set to ‘on’ i.e. you have programmed it to come on between 7pm and 9pm for example and secondly that the zone it is connected to is below temperate. So in this instance if the zone is set to be 21c but the room is only 19c and 7pm, then the system will call for heat.

Because 2 things need to be true, you switch the the heating controller / timer clock to constant mode, and then set the times that you want the zone to heat in the tado app. For example, if you want your main bedroom to be 21c between 8pm and 10pm at night, then set the Tado app as such. If the bedroom is 19c at 8pm, then the smart radiator thermostat will call for heat, and if it is correctly matched to the smart thermostat upstairs, then that will click and the boiler will start.

Because the downstairs smart thermostats are wired, they by pass the heating controller / timer clock - and call for heat independently.

Its a long answer, sorry, but I’d start by making sure that the heating controller / timer clock is set to constant mode, that the smart radiators are linked to the correct wired thermostat in the app and that each room is set up correctly. You can check this by going to Setting / rooms and devices / and then click on the room. It will show you the measuring device for that room and additionally the zone controller it uses to call for heat.

every system is different, so i hope that this helps.

Mickyman

A quick test to see if the tado receiver has control of the boiler is to press the ch test button on the the receiver. Your boiler should toggle on and off each time you press the switch. The power led will go amber whilst testing but will go white again after about 2 minutes from the last button press.