Nest Heat Link has died - no power getting to it

[Kraven10]

My 3rd gen heat link is hardwired to the mains but has just stopped working.

There are no lights showing at all.

I've had tried to reset it by pressing the button for 10 seconds and then 30 seconds but it is definitely dead as no lights are showing.

The thermostat is displaying a H72 Heat Link error message.

How do I get a replacement please?

Thanks

[puddatoo]

Hopefully my issue with this will help you.

I came home to a house at 39 degrees. In troubleshooting the H72 error I discovered that with no common wire from the furnace to the thermostat the internal battery is only charging when the furnace was running. This wasn't enough to keep the battery charged and it eventually ran below the operating voltage.

I installed the old thermostat temporarily and ended up running a 5 wire thermostat wire ( in doing so I discovered a cross colored wire error at the furnace that explains the installation assistant telling me to reverse the wires at the thermostat base- very smart).

The back of the learning thermostat has a plug for charging however it can't be plugged into the base while doing so. 

I've since installed a Nest E (retired and not traveling to work any longer) that is working fine. The learning thermostat is still in my Home but used as a remote thermostat only as I'm not trusting the rechargeable internal battery after so long of not charging correctly.

https://support.google.com/googlenest/answer/9248732?hl=en-GB#zippy=%2Ch-or-h

[Kraven10]

Thanks for your response.

My thermostat is currently working fine and still has a limited charge although, it's displaying the H72 error.
My issue primarily is with the heat link next to the boiler. It appears to be dead and as such is not talking to the thermostat to control the boiler.

[AlexD]

Thanks for reaching out to us here @Kraven10 . I am sorry to hear you are facing difficulties with your device and I would be happy to try and assist. If you haven't already, check the breakers and switches at the location, to make sure nothing has tripped. Also check the boiler as it can sometimes have a separate switch on it. Confirm it has power, it should have a display or LED that turns on.

If it all looks good try and power cycle the Heat Link, if you're comfortable in doing so. Turn the power to the Heat Link off for a few minutes and then turn it back on. See if it has any reaction after, when you press the button on it. 

Also let us check a few things:

1. When was the thermostat installed?
2. When did you first notice this behaviour?
3. Was it installed by a Nest Pro or by a heating/electrical engineer?
4. Did you notice any power cut in the area before this occurred?

5. Did you have any maintenance done on the heating or electrical system recently? 
6. Do you have only one or multiple Google Nest thermostat devices at the location?

[Kraven10]

Hi Alex

Thanks for your response.
The breakers and switches are all on and functioning normally. The power to the boiler is working fine and I still get hot water.

I have switched the Heatlink power on and off and pressed the button but there is no response or lights.

1. The thermostat was installed a year ago

2. The behaviour started on 12 November (2 days ago)

3. It was installed by a Nest Pro

4. There was no power cut prior to the event

5. There has been no maintenance or power loss in the area
6. I had no recent maintenance on the heating system
7. I have only one Nest Learning Thermostat at my location

[AlexD]

Thanks for checking. In that case I'd like to create a case for you so we can check the warranty and some details. Would it be ok if I reached out to the email you have associated with your account here?

[Kraven10]

Yes, no problem.

[AlexD]

I sent the email your way. Once you go through the form let us know here so me or one of my colleagues can check for it. 

[Vladut]

Hi there, just checking in with you. Did you manage to check our last message?

[Kraven10]

Hi 
Yes, I received the email and submitted the information the same day.

[Vladut]

Can you please fill it again?. I cannot seem to find it.

[Kraven10]

I have completed it again.

[TudorL]

Thanks for completing the form again. Now, it seems that the serial number you provided is not the right one, as the system works with the one on the back of the display, the one that starts with 09, but I'll send you an email right away so that you can provide the correct serial number over there. 

[LarisaL]

Hi there, just checking in! Have you seen the message from my colleague?

[Kraven10]

Hi
I submitted the form again and I just replied to the email.

[AlexD]

Thanks, got it. I sent an email your way with more information. Check it out and reply to it if you have any questions.