Heating constantly on despite thermostat being turned off

[Fivestack]

Our heating is constantly on all of a sudden. We had a water leak a week or so ago and had water come through the ceiling. The living room light had to be removed(it was full of water) and it turns out our boiler is in the same lighting circuit as said downstairs lights. Since it was all dried out and light has bee  re-fitted our boiler is now constantly on despite tge nest saying the heating is off. I've reset the thermostat to factory defaults and re paired the heat-link but still the same. Just having to actually switch the boiler off atm which is not ideal. Any suggestions?

[AlexD]

Thank you for reaching out to us here @Fivestack . I would be happy to try and assist. 

FIrst it would be best to try and do a test on the Heat Link, to see if it is working as expected. Open up the Nest app on your mobile device and go next to the Heat Link, the white box.

Make sure the heating is turned off, the screen is black in the Nest app for heating control, and turn it up until it goes orange. Listen for a click noise from the Heat Link. After turn the temperature down until it goes black and listen for a clicking noise again from the Heat Link.

If the Heat Link clicks in both cases that would indicate it is working as expected, as it should click it changes states from on to off for both heating and hot water. 

If this is the case it is most likely something else in the system like the wiring, a valve or the boiler itself that is causing this behavior most likely. It would be best to get in touch with your preferred installer or a Nest Pro to have a look at the system and give you a diagnostic report. 

[Fivestack]

I've tested it and the heat link definitely clicks when I turn the temp up or off. Still the boiler is flat out heating the radiators. Now it can't be a wiring issue surely if its been working totally fine for about a year now. 

[DragosC]

Thanks for letting me know @Fivestack. Could you provide me please with a few pictures of the wiring just in case? If the Heat Link clicks, it means it's sending the signal to the boiler. 

[Fivestack]

The wiring is fine. Has been working for nearly a year so far. RESOLVED  The problem is the Hot water. Soon as I turned off the hot water (which was set to be constantly on) the radiators went cold and the boiler stopped firing. Turned my thermostat up and the boiler fired uo again. Seems like a valve problem and not related to my thermostat at all. When the hot water is on its feeding my radiators. Keeping them on constantly. Sounds like a failure of the 3 pipe junction that feeds the hot water from the boiler. 

[CristianC]

Hey @Fivestack. I'm glad to hear that you resolved the issue. I'm going to lock this thread now. If anything comes up, feel free to open a new one.