topic Re: Cannot start nest thermostat to pair with heatlink in Nest Thermostats

Cannot start nest thermostat to pair with heatlink

Bgduggan — Sat, 11 Dec 2021 18:56:21 GMT

The heat link keeps clicking and blinking

Thermostat cannot pair

Cannot get to settings from set up to get code for app

Just keeps trying to pair and failing

Turned on and off, but just lands on set up and continues cycle

Any advice appreciated 🙏

Re: Cannot start nest thermostat to pair with heatlink

Frustratedddd — Sun, 12 Dec 2021 17:16:54 GMT

Looks like everyone rushing to help you!!!

Your description does not make a lot of sense to me!

Just to confirm.

What colour lights on the Heat Link, and how many?

What do you see on the display, anything?

Forget the App to start, you want the pairing working first.

Re: Cannot start nest thermostat to pair with heatlink

Bgduggan — Sun, 12 Dec 2021 17:31:22 GMT

Hey Frustrateddd

You're right, the response is over whelming!

My description probably didn't help though

My electrician wired the heat link and I foolishly said I would do the set up

Have Google hub, nest doorbell and mesh WiFi which all went together without issue

The thermostat is on a stand and when I started the set up the qr code wasn't recognised but started the steps anyway. Got as far as pro set up and pairing which it cannot do. Just reads H71 error. I went onto the app for advice and it says I need a code from the thermostat settings - but I cannot get the thermostat to go back to the home screen and access settings. It just tries to pair or let me look at the spec

When I pressed the middle button on the heat link the blue light at top went off then the two lights below (3 lines and a water droplet) flash on green a clicking sound like a switch starts and then they go off. This repeats ever 5 seconds until I turn the boiler off

Currently the boiler is and and producing heat and water but there's no control so we either have dull heating turn it off

Grateful for your feedback

Re: Cannot start nest thermostat to pair with heatlink

Frustratedddd — Sun, 12 Dec 2021 18:53:05 GMT

Ok, first off all the other items you mention for get them for now, that just complicates things, just work with the thermostat.

1. The first thing you need is the blue pulsing light ONLY, if the others are on, press the button so the blue pulsing light is the only light. Then, just to double check, when you have the blue light pulsing, press and hold the Heat Link button for about 30 seconds, wait until the blue light comes back on and a steady pulse again. Do that twice, this is just a make sure it's ready method.

2. The display, does it show on the screen something like this.

Check Again

Reset Pairing

Replace Heat Link

Tech Info

Should the answer be yes, go to Tech Info and check the 6 digit code under Heat Link. Make a note of that number, then return back to the screen.

Take a look at 6 digit code on your Heat Link found by the left hand fixing screw, or on the Heat Link lid by the screw. Does that number match the number you wrote down?

Answer Yes, go to the display and click, Reset Pairing, let it search for the Heat Link

Answer No , go to the screen and click Replace Heat Link - Enter the 6 digit number - When you get to continue, do NOT click continue, leave for a couple of minutes. After a couple of minutes, then click continue, the display will search for the Heat Link.

See what happens.

Re: Cannot start nest thermostat to pair with heatlink

Bgduggan — Sun, 12 Dec 2021 20:54:40 GMT

Many thanks, I have followed those steps and end up in the same place.

I am beginning to think that the heat link is broken?

When I hold down the centre button on the heat link the blue light comes on as a slow pulse, but when I take my finger off it returns to the clicking and flashing green lights. I have repeated this step for varying lengths of time but the result remains the same

The numbers on the heat link and logged in the thermostat are the same.

The clicking sounds like it is attempting to do something, just unsure what

Re: Cannot start nest thermostat to pair with heatlink

Frustratedddd — Sun, 12 Dec 2021 21:13:02 GMT

This is a new one on me! After fitting several hundred Nest thermostats I have not had this problem.
can you take a picture of the heat link wiring if possible?

Re: Cannot start nest thermostat to pair with heatlink

Bgduggan — Mon, 13 Dec 2021 07:15:15 GMT

Cannot see an option to attach a photo to this forum

I have taken the cover off and am mildy concerned by my electrian

There are only 2 wires connected:

The Blue wire in the Neutral

The Brown wire in the Live

The Earth is not attached to anything

No other wires are in the unit. It is going into a Vaillant combi boiler

Heading into work this morning and going to look up a nest help line as I think this is a parts issue?

Re: Cannot start nest thermostat to pair with heatlink

Frustratedddd — Mon, 13 Dec 2021 09:49:33 GMT

Oh dear, that’s sounds a wonderful install.

the power in should go Neutral to the far left, then 2nd from the left Live feed. The earth should be fitted far right hand side clearly marked earth.
You should also have at least a loop connection from the live to terminal 2, which gives power to the heating contacts. You should also have a connection out from at least terminal 3 on a standard simple boiler.

I would suggest without the most important connection on any installation NOT connected, you get your money back. The earth is the most important connection. The heat link is a double insulated accessory, but you don’t just leave an earth cable floating about!

Why your relays are chattering is odd. Are you sure the only connections are L&N? No loops out of the other terminals at all?

I just had a thought, I wonder if the craftsman has used a feed from the boiler some how!!

I would get this checked quickly, or at least isolate the Heat Link.

Re: Cannot start nest thermostat to pair with heatlink

AnaM — Tue, 14 Dec 2021 13:59:25 GMT

Hey @Bgduggan,

I'm sorry to hear about your issue and also, I apologize for such a delayed response. I'd like to help out now if it's still needed.

The wiring that you described above does not seem to have been done according to our installation guide. Here's the link for it, maybe it will help you figure out what kind of wiring the installer attempted to do: https://bit.ly/3nt2N4t.

A picture would be needed to figure out what's not done correctly, and once we make sure the wiring is fine, we can troubleshoot the other parts of the Nest system.

If you are unable to send us a picture here, you can try to reach us on other support channels. Here is our phone number: 0808 169 2307. We are available Monday to Friday – 08:00‑19:00, and Saturday to Sunday – 09:00‑17:00. You can also reach us out on social media or on our Live Chat Support. However, you should be able to attach a picture to this forum thread as well.

Re: Cannot start nest thermostat to pair with heatlink

AlexD — Sun, 19 Dec 2021 11:13:30 GMT

Hi, I wanted to check in. Do you need any further assistance?

If so, make sure to let me know.

Re: Cannot start nest thermostat to pair with heatlink

Bgduggan — Sun, 19 Dec 2021 12:54:20 GMT

Hello to all

Apologies for a slow response. This time of year is a bit hectic for me at work, so this slipped down my to do list

All issues are now resolved, thankfully. The forum was very helpful in pointing out concerns with my electrians installation. I brought in a nest recommended installer, to have it correctly wired (both the heat link and the boilers itself were incorrect) - the electrian had also wired the doorbell incorrectly (to high voltage!) Apart from that he did a great job!!

I appreciate the time all of you took to respond and get me in the right direction. It does help

Merry Christmas

Re: Cannot start nest thermostat to pair with heatlink

Frustratedddd — Sun, 19 Dec 2021 14:32:54 GMT

Ah, the crafstmen of today, don't you just love their talents!!!

Re: Cannot start nest thermostat to pair with heatlink

Bgduggan — Mon, 20 Dec 2021 19:23:47 GMT

Honestly worry for the future!

Re: Cannot start nest thermostat to pair with heatlink

AlexD — Fri, 07 Jan 2022 13:22:58 GMT

It is great to hear that things are back on track now @Bgduggan . Should anything else come up, make sure to start a new topic/post. I will go ahead and lock this thread down.