topic Re: Nest Gen 2, heat link error H72 in Nest Thermostats

Nest Gen 2, heat link error H72

JillP — Thu, 18 Aug 2022 17:52:18 GMT

After working fine since I moved in (Nest was already installed in the house) - I now get an H72 error from the thermostat. heat link doesn't have any lights on. The same plug works the boiler and that's fine...no change since it worked previously - now it doesn't work - I've tried 20+ second reboot, but doesn't do anything, no lights on - any ideas welcome, thanks

Re: Nest Gen 2, heat link error H72

george_t — Fri, 19 Aug 2022 10:52:50 GMT

Hi @JillP. I'm sorry to hear you're experiencing this issue, but we'll sort this out together. Let's start with a few questions:

What type of Nest thermostat do you have?
Did the issue happen during installation or after installation? Was it installed by a Nest Pro or by a regular installer?
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?
Have you tried any troubleshooting steps before contacting us?
How many thermostats do you have?

Re: Nest Gen 2, heat link error H72

JillP — Fri, 19 Aug 2022 17:29:55 GMT

What type of Nest thermostat do you have? Gen 2
Did the issue happen during installation or after installation? After ...it has been working fine, no power cuts

Was it installed by a Nest Pro or by a regular installer? I don't know, was here when I moved in, has worked fine for 18 months until suddenly getting the H72 error message
Are there any lights on the Heat Link? No

Does the boiler activate when calling for heat by pressing the Heat Link's button to activate Manual Mode? I don't know what this us/how to do this...pressing button on the middle of the heatlink dies nothing
Are you seeing any wiring report or error on the thermostat and/or the app? Just the H72, no power message
Have you had any recent power cuts in your area? If yes, has the power been restored?
No power cuts or power disturbances detected elsewhere
Have you recently had service or maintenance on your electrical, plumbing, or heating system? No
Have you tried any troubleshooting steps before contacting us? Checked the power source/fuse to the heatlink, Googled....nothing else
How many thermostats do you have? 1

Re: Nest Gen 2, heat link error H72

JillP — Fri, 19 Aug 2022 17:30:07 GMT

What type of Nest thermostat do you have? Gen 2
Did the issue happen during installation or after installation? After ...it has been working fine, no power cuts

Was it installed by a Nest Pro or by a regular installer? I don't know, was here when I moved in, has worked fine for 18 months until suddenly getting the H72 error message
Are there any lights on the Heat Link? No

Does the boiler activate when calling for heat by pressing the Heat Link's button to activate Manual Mode? I don't know what this us/how to do this...pressing button on the middle of the heatlink dies nothing
Are you seeing any wiring report or error on the thermostat and/or the app? Just the H72, no power message
Have you had any recent power cuts in your area? If yes, has the power been restored?
No power cuts or power disturbances detected elsewhere
Have you recently had service or maintenance on your electrical, plumbing, or heating system? No
Have you tried any troubleshooting steps before contacting us? Checked the power source/fuse to the heatlink, Googled....nothing else
How many thermostats do you have? 1

Re: Nest Gen 2, heat link error H72

george_t — Sat, 20 Aug 2022 14:20:46 GMT

Thanks for the details, @JillP. I'll be reaching out to you via private messaging so we can gather some more information securely to continue helping you over email. Once you complete and submit the requested form sent to you on DM, please send a short reply on the public thread so I can search for it. Thanks again.

Re: Nest Gen 2, heat link error H72

JillP — Sun, 21 Aug 2022 08:01:30 GMT

Hi, I've replied to your email and filled in the form with the further details requested...

Re: Nest Gen 2, heat link error H72

george_t — Sun, 21 Aug 2022 08:34:24 GMT

Thank you for submitting the form, @JillP. I have sent you an email with the next steps. Let me know if there is anything else I can help you with.

Re: Nest Gen 2, heat link error H72

AndaD — Wed, 24 Aug 2022 09:40:30 GMT

Hey there @JillP, just checking to see if you managed to find the email from us. Let me know if there's something you need help with.

Re: Nest Gen 2, heat link error H72

JillP — Wed, 24 Aug 2022 12:46:41 GMT

Hi, someone from Boxt came over yesterday, but, despite providing a new unit and the heatlink now has lights etc.. he said it's the wiring overall that's wrong and would get back to me.

The wiring for the boiler and Nest (they are on the same switch) have worked fine until now, so I'm worse off as the wiring had to be exposed, casing taken apart for this, quite messy and still not working thermostat and no indication as yet as to what's going to be done.. could you help please?

Re: Nest Gen 2, heat link error H72

AndaD — Wed, 24 Aug 2022 15:57:58 GMT

@JillP

I'm sorry to hear about this uncomfortable situation, but let's clarify a tiny bit in order to avoid confusion. You mentioned that your Heat Link has a green light on but your thermostat isn't working, how come this happened? Also, I'm trying to understand what's wrong with the wires. Is there any chance to provide me a couple of pictures so I can have a better picture of the environment/situation? It will help me see what's happening.

Re: Nest Gen 2, heat link error H72

JillP — Thu, 25 Aug 2022 06:57:54 GMT

Hi, the Boxt engineer changed the heatlink...the new one seems to be working, it has the lights on at least. It didn't communicate with the thermostat still (thermostat still had the H72 error )

Boxt fitted a new thermostat, it still has the H72 error. He said they have always connected before, the heatlink and thermostat.

He then looked in the switch for the supply to the heatlink and said their were problems with the wiring and left...he did take pictures, I'll try and get them from him...I'm not keen on undoing this socket myself as he says there's 'something wrong' with it!!

Re: Nest Gen 2, heat link error H72

JillP — Thu, 25 Aug 2022 07:04:23 GMT

here's the picture

Re: Nest Gen 2, heat link error H72

AndaD — Thu, 25 Aug 2022 16:01:56 GMT

@JillP

Thanks a lot for explaining the whole situation. Since an electrical specialist was on the site and checked all the wires, I'll recommend you to wait until they get back and sort it out. What I can offer you at the moment is technical support for your thermostat, but I am unable to do anything remotely with the wires.

Can you tell me if your thermostat is wall mounted or on a stand?

Re: Nest Gen 2, heat link error H72

JillP — Thu, 25 Aug 2022 17:14:10 GMT

Hi, the thermostat is wall mounted.

I haven't heard anything from boxt as to when/if they're coming back re the wiring...

Re: Nest Gen 2, heat link error H72

AndaD — Fri, 26 Aug 2022 08:06:55 GMT

@JillP, I'm sorry to hear this. Did they give you any reference number by any chance? Also, you can try to contact them once again by using your Case reference number provided by us. Keep me posted on how it goes.

Re: Nest Gen 2, heat link error H72

JillP — Fri, 26 Aug 2022 08:40:04 GMT

Hi, I don't have a reference number, but I called Boxt and they are going to send a different engineer to look at it next Wednesday - which is the earliest they can do

Re: Nest Gen 2, heat link error H72

AndaD — Fri, 26 Aug 2022 08:53:36 GMT

@JillP

The good part is that they're going to fix this asap. I'm glad to hear that you managed to get in touch with them. What's the state of the thermostat at the moment? Could you please provide me a picture with the display and its placement?

Re: Nest Gen 2, heat link error H72

JillP — Fri, 26 Aug 2022 18:15:30 GMT

Hi - they are saying that if it's the wiring, they won't fix it - even though everything WAS working fine...it's been left in a mess and not working, so I'm worried I have to now get the wiring looked at - but they're sending someone else on Wednesday, so will see what they say...
The thermostat runs out of battery where it is placed in the hallway - when it's charge by USB it still says that there's not power to the heatlink and error code H72.

Pics of the thermostat after USB charging, and the heatlink - which now has a flashing blue light (there were no lights before they came). These are replacement heatlinks and thermostat, so brand new...

Re: Nest Gen 2, heat link error H72

JillP — Fri, 26 Aug 2022 18:16:39 GMT

Re: Nest Gen 2, heat link error H72

AlexD — Sat, 27 Aug 2022 10:59:07 GMT

Thanks for all the information. I am sorry to hear they were not able to get everything back on track right away. Hopefully they can see what's going on when they come over and get things back on track. When the engineer is there you can reach out to us on our live support line over chat or phone and we can assist with any checks and troubleshooting if needed live with them. Here is the link with the contact information so you have it on hand: https://goo.gle/30rMwmy .