Nest not turning the hot water

[Aleksr]

Over the last few days I noticed that the hot water doesn't turn on unless the heating is turned on at the same time, be it scheduled or boost. Can you please advise on how to fix it?

[AlexD]

Thanks for reaching out to us @Aleksr . I am sorry to hear you are facing difficulties with your thermostat and I would be happy to try and assist. 

I want to do some tests to see how the relays in the Heat Link behave. Go next to the Heat Link and open the Nest app on a mobile device:

1. Select your thermostat to access the heating controls and make sure the screen is black, heating is off.
2. Turn up the temperature until the display goes orange, heating on, and listen for a clicking noise.
3. Turn the temperature back down until the display is black again, heating off, and listen for a clicking noise again.

On the hot water side:

1. Go to the Nest app and select the hot water control.
2. Tap on the cogwheel in the upper right corner to go into the hot water settings and toggle the first option there off. This will turn off the hot water schedule, you can enable it back after the test.
3. Boost the hot water for any amount of time and listen for a clicking noise.
4. Turn the boost off and listen for a clicking noise again.
 

Let me know what the results are. 

[AlexD]

Hi, I wanted to check in. Did you get the chance to do the test? Keep me posted. 

[Aleksr]

There is a click on turning on and off both heating and water.

[TudorL]

By any chance, do you have a system boiler with a separate hot water tank and a Y-plan or a three-port valve?

[Aleksr]

I think so

[Vladut]

In this situation, based on what you've described so far, it seems like the thermostat it's working as it should so the next thing to check will be the wiring, valves and boiler. And for that you'll need an installer. Do you have the means to contact one?

[Aleksr]

No I don't, not aware of any installers - we bought the house with nest already installed.

But the boiler has been serviced a couple of months ago. The hot water works, just doesn't seem to be triggered unless the heating is on. And we have not had this issue until a couple if weeks ago.

[LarisaL]

Hi there. If you don't know any installers, you can reach a Nest Pro installer and they can check the valves, boiler and the wiring for you. And because this might be happening because of various reasons, we perform a click test to determine if the issue is related to your thermostat or to another part of your heating system like a valve, wires or with the boiler itself. Please go near your Heat Link and turn the boost for hot water on from the app and let me know if you hear a click. You should hear a click when you turn on the boost and another click when you turn it off. Just to make sure that the relay is working properly, please try that 5 or 6 times and let me know if you hear a click at every command.

[Vladut]

Hi there, just checking in with you. Did you manage to check the last mssage?

[TudorL]

Hi there, since me or my colleagues haven't heard from you in a while, we'll need to close this thread, but you can always open a new one if there's any active issue. Have a good one and stay safe!