topic Re: Advice Please in Nest Thermostats

Advice Please

JustinD — Fri, 19 Nov 2021 13:13:47 GMT

Hi All

I've moved into a rented property with two Nest Gen 3 learning thermostats (Display-3.4 models). These are linked to an Ideal Logic System 18 boiler via two separate Heat Links (Amber-2.5 models).

I did a hard reset of the thermostats to clear the old residents data. On doing so I was asked about the set up and tried to input "Open Therm" (as the boiler seems to be Open Therm compliant) but it said that there wasn't the correct connection, so I chose "On/Off".

However, even with the thermostats set low or off, the boiler chugs away merrily with a status being shown on the LED control panel of "c" - which means "heat being supplied" even though the burner light is off (so I assume no heating is actually taking place).

The boiler does not go into standby mode at all (which would be a "0" on the status LED).

It seems to be using quite a lot of gas despite very little heating being supplied (the house is very well insulated).

Has anyone seen anything similar? Am I doing something wrong or, perhaps, it's not wired up correctly?

Thanks in advance.

Re: Advice Please

CristianC — Wed, 01 Dec 2021 17:07:50 GMT

Hi @JustinD,

Thanks for reaching out. Just to confirm, the issue is that your heating turns on unexpectedly? Can you check if it's because of your schedule? If you have the learning feature active, it will create a schedule.

Re: Advice Please

AlexD — Fri, 10 Dec 2021 16:10:51 GMT

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

If so, make sure to let me know.

Re: Advice Please

JustinD — Sat, 11 Dec 2021 16:09:48 GMT

Hi Christian. Thanks for your reply. No, it’s just that the boiler never goes into standby mode - even when the thermostats are off it still thinks they’re on but have reached the right temperature. So, the boiler’s waiting for the temp to drop (vs turning off). Does that make sense? Justin

Re: Advice Please

JustinD — Sat, 11 Dec 2021 16:10:51 GMT

Hi @AlexD please see my reply to @CristianC J

Re: Advice Please

AnaM — Mon, 13 Dec 2021 18:49:41 GMT

Hey @JustinD,

Thank you for the clarification. I have a few questions for you:

Do the thermostats communicate with the Heat Links as expected? Does the heating turn on and off as it should?
Does one or both of the displays show the heating on all the time?
Has this always been an issue?
When were your thermostats installed?
Did you make sure neither thermostat was calling for heat when you checked the boiler?

Re: Advice Please

JustinD — Tue, 14 Dec 2021 12:06:27 GMT

Hi @AnaM

Do the thermostats communicate with the Heat Links as expected? Does the heating turn on and off as it should?
- Yes & yes - though as above, the boiler is constantly showing "c" on the display - which means it believes that the thermostat is on but has reached the desired temperature, even when both thermos are actually off (when one would expect the boiler to show "0" on the display and go into full standby mode). The temp goes up and down as required via the thermos, so it's working fine - I just have this niggle that the boiler's never going into full standby mode
Does one or both of the displays show the heating on all the time?
- No, both are behaving normally with the orange background showing when rising to the set temp and going off when that is achieved. The thermos can be turned off as normal
Has this always been an issue?
- I only moved in at the beginning of October (rented property). I reset both thermos when I moved in - so I could connect to my own account and to clear the old schedule.
When were your thermostats installed?
- Again, not sure but after 2019
Did you make sure neither thermostat was calling for heat when you checked the boiler?
- Yes

Re: Advice Please

AnaM — Tue, 14 Dec 2021 13:12:48 GMT

Thank you for your answers @JustinD.

Can you take a picture of the Heat Link wiring? It would give me a clearer image of how the boiler is expected to work.

Re: Advice Please

JustinD — Tue, 14 Dec 2021 16:03:19 GMT

Re: Advice Please

JustinD — Tue, 14 Dec 2021 16:03:45 GMT

Re: Advice Please

JustinD — Tue, 14 Dec 2021 16:04:13 GMT

Re: Advice Please

AnaM — Tue, 14 Dec 2021 16:42:56 GMT

Hey @JustinD,

Thank you for the pictures. Would you be able to take the cover off? Only if you feel comfortable doing so as that's where you can see the terminals and the wires.

Re: Advice Please

JustinD — Tue, 14 Dec 2021 16:55:24 GMT

Does this work? Shows both Heatlinks and the junction box.

Re: Advice Please

AnaM — Tue, 14 Dec 2021 17:33:54 GMT

Yes, that's great, can you send a picture taken of one of your Heat Links closer, so that I can see all the terminals?

Re: Advice Please

JustinD — Tue, 14 Dec 2021 17:40:55 GMT

Here you go:

Re: Advice Please

AnaM — Tue, 14 Dec 2021 18:17:51 GMT

Thank you, @JustinD.

From what I can see, everything seems fine with the wiring, at least concerning the Heat Link terminals. Let's do a test, go next to the Heat Link and call for heat from your Nest app, listen for a click. Turn it off and listen for a click again. Do the same for the Hot Water if you use it to control that as well. Let me know what the results are.

Re: Advice Please

JustinD — Wed, 15 Dec 2021 12:22:12 GMT

Yes, clicks when calling for heat and turning off for both thermos. Also when turning the hot water off and on.

Re: Advice Please

AnaM — Wed, 15 Dec 2021 13:34:43 GMT

Hey @JustinD,

Alright, thank you for doing this. Based on all the information provided, the Nest system seems to be working as expected. The wiring on the Heat Link also seems done correctly as far as it concerns the terminals, which means that you should reach out to an installer to have your boiler and the other parts of your heating system checked.

Re: Advice Please

JustinD — Wed, 15 Dec 2021 13:51:13 GMT

Thank you!

Re: Advice Please

AnaM — Wed, 15 Dec 2021 14:00:47 GMT

It's been my pleasure to assist you on this matter. If you need anything else, feel free to reach out to us on any support channel you prefer.