topic Re: No light on heat link in Nest Thermostats

No light on heat link

LEEDS-UK — Tue, 11 Jan 2022 15:35:38 GMT

I have no light on heat link and display showing error H72. We had it more then a year working fine and yesterday night it stops. We had no power cuts no other electrical issues in the house. We tried to switch boiler on and off and all electricity at home. No results. Its getting really cold and I need your urgent help please.

Re: No light on heat link

CE07 — Wed, 12 Jan 2022 10:26:16 GMT

I have had the same problem: although power to heat link was ok there were no outputs and I was getting the H72 message, which means no power to the stat. Came to the conclusion that the heat link was dead. Due to weather I couldn't be without heat for several days so I installed a new one and everything ok. Contacted Nest to get the heat link replaced as less than 2 years old, so at least I'll have a spare. However as it's disconnected they want me to get an electrician's diagnostic report. I've explained there were no lights on and the unit was unresponsive; even offered to send it back to them at my cost for examination but no go. I've lodged a complaint so await their response. They are very uncooperative, want to go through their trouble shooting protocols (difficult when the unit is dead?) and treat folk like idiots, so be warned.

Re: No light on heat link

CristianC — Wed, 12 Jan 2022 14:03:26 GMT

Hello @LEEDS-UK,

Thanks for reaching out. I'll do my best to get this sorted for you as soon as possible.

Here are some helpful troubleshooting steps:

Press the button on the Heat Link and check if you have any lights on it
Check if the circuit breakers and the switches are set to on
Turn them off and then back on
Press on the button again and check for LEDs

Could you also help me with some answers to these questions?

How long has your thermostat been installed for?
Did the issue happen during the installation?
Is there any error on the Nest thermostat display?
Have you had any power cuts recently?
Have you had any work done on your electrical or heating systems recently?
If yes, was the power properly restored at the fuse board after work was done?
How many zones ( thermostats ) are present in the setup?

Regards,
Cristian

Re: No light on heat link

CristianC — Mon, 17 Jan 2022 11:37:03 GMT

Hello again. Just checking in. How's it going with your Heat Link?

Re: No light on heat link

CristianC — Wed, 19 Jan 2022 11:37:56 GMT

It's been a while since this thread was last updated so I'll go ahead and lock this thread. If you're still experiencing problems, please feel free to start a new thread and we'll be happy to help.

Re: No light on heat link

KarlJoones — Thu, 10 Feb 2022 18:29:07 GMT

Having this exact same conversation with Nest. Disconnected as it is in the middle of winter, and they want me to pay to get another engineer out to do a diagnostic report at my own cost, despite the heating working with the nest disconnected.

@CristianC OP already stated that this is not connected, and has likely gone through all the troubleshooting steps. Please read the previous messages.

Re: No light on heat link

DragosC — Fri, 11 Feb 2022 11:08:09 GMT

Hi there all.

Thanks for letting us know.

Could you tell me please when did the situation start occurring first and when was the thermostat installed?

Also, please answer to the following questions:

Are there any lights on the Heat Link? Does the boiler activate when calling for heat by pressing the Heat Link's button to activate Manual Mode?
Are you seeing any wiring report or error on the thermostat and/or the app?
Have you had any recent power cuts in your area? If yes, has the power been restored?
Have you recently had service or maintenance on your electrical, plumbing, or heating system?
If yes, how long was the power off for? (Be specific.)
Could you tell us please if you've checked on the breaker switch and fuse box?
Any blown fuse in there? Have you tried to turn the breaker switch off and on again? Any difference?

Re: No light on heat link

CristianC — Mon, 14 Feb 2022 12:23:17 GMT

Hello again. Just checking in. Do you still need assistance?

Re: No light on heat link

CristianC — Wed, 16 Feb 2022 12:31:32 GMT

Hello again. It's been a while since this thread was last updates so I'm going to lock it. If anything comes up, feel free to open a new one.