topic Re: Nest thermostat runs only in manual mode for heating in Nest Thermostats

Nest thermostat runs only in manual mode for heating

bbbiby — Thu, 06 Jan 2022 12:38:54 GMT

The thermostats have been working fine till this morning. When I try to turn the thermostat up, it turns orange as expected and there is a "click" on the Heat Link. However nothing happens on the boiler. The thermostat then sits showing the room temp "18*C" and the desired temp "21*C" as if it is working away correctly. This is also shown in the app on my phone too.. The same circumstances happen when I use the app to change the temperature... Both app and thermostat update each other but do nothing to the boiler.

The home link when ran in manual mode, works absolutely fine. I can press the button and it fires the boiler without any issues. So at least the house is warm.

I have seen no error codes and have restarted both the thermostat and Heat Link to no avail. This is a wire connection btw, and the heatlink shows all three lights as green when in manual mode as well.

Unsure what to do here. Any help?

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Thu, 06 Jan 2022 16:39:59 GMT

You can hear the heat link click when the display is turned both ways, correct?

Would you be able to check the connections in the heat link? You only need a neon type tester or something to check the power.

You need to put the neon tester on terminal 1, and see if a bright light shows when NOT calling for heat, and then terminal 3 should be a dim light.

Then turn the display to call for heat, and then test terminal 3 should be bright light, and terminal 1 should be dim.

Would that be possible to check where we are to start with?

Re: Nest thermostat runs only in manual mode for heating

bbbiby — Fri, 07 Jan 2022 10:20:40 GMT

Will try it out today with my electrician! I also heard that this may be caused due to faulty valves sooooo we`re gonna try all.

Re: Nest thermostat runs only in manual mode for heating

Frustratingnest — Fri, 07 Jan 2022 20:48:22 GMT

I have exactly the same issue. The thermostat has been working fine for a few years until yesterday morning.

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 03:20:57 GMT

Me too have the exact same issue . Only one think which I can do from phone is the booster mode for hot water works fine. 🤦‍♂️ Tried explaining to the Google support and they send me a new heatlink but no use… still the problem continues…

Re: Nest thermostat runs only in manual mode for heating

bbbiby — Sat, 08 Jan 2022 10:41:32 GMT

@Josemaskil and @Frustratingnest my electrician did a few checks yday, and we re taking it baby steps. it seems that 2 eph valves MAY be not working as expected so next week the plumber will come to change. I will let you know if that was the problem or something else needs to get checked or changed.

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 12:43:04 GMT

I tried with a neon tester and when calling for heat through phone there are no changes.

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Sat, 08 Jan 2022 13:21:20 GMT

I would suggest before trying the phone you use the display dial to call for heat.

There could be an issue with the connection from the phone to the thermostat! You are trying to prove the heat link is talking to the display.

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Sat, 08 Jan 2022 13:22:21 GMT

The easy prove is as mentioned, check the relays. That will then prove if the Nest is working correctly.

You can then eliminate the Nest part before you start.

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 13:34:44 GMT

I tried and the thermostat is not communicating with the heatlink. I can hear a click sound in the heatlink when calling for heat from the thermostat.

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Sat, 08 Jan 2022 14:10:39 GMT

I'm confused!

You say, when the display is turned to call for heat and the screen goes orange, you hear a click in the heat link - correct?

When the dial is turned the other way, and the screen goes to black, you hear another click - correct?

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 14:26:32 GMT

Yes

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Sat, 08 Jan 2022 15:17:12 GMT

OK, that means the thermostat is talking to the heat link some how, the next question is - Hard wired or just wireless, or both wired/wireless?

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 15:22:23 GMT

Hardwire

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Sat, 08 Jan 2022 15:39:06 GMT

To sum up, You are hard wired, and the thermostat works fine with the display, correct?

You can Boost the HW from the phone, and that works fine, correct?

Have you tried to set the Display to the Heat Link wireless?

What did you find when you tested with the neon on terms 1&3 and 4&6 manually with the display?

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 15:51:36 GMT

When checked the with neon tester in manual mode terminal 1 dim light and terminal 3 bright light and terminal 4 dim and 6 bright light.

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Sat, 08 Jan 2022 16:20:07 GMT

That is correct. Now when you turned the dial for calling for HEAT, and the display went to orange, what were the terms 1 & 3?

Terms 4 & 6, what happened to those when you called for HW - ie Boost?

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 16:27:53 GMT

1 is dim and 3 is bright and HW time 4 dim and 6 bright another thing just happened is steady green light (the power)is sort of slowly blinking

Re: Nest thermostat runs only in manual mode for heating

Frustratedddd — Sat, 08 Jan 2022 16:37:00 GMT

That means the relays are not switching. I take it you have a live feed in terms 2 & 5?

The green light at the top should be a steady green light, no blinking.

Can you upload a pic of the heat link connections?

Re: Nest thermostat runs only in manual mode for heating

Josemaskil — Sat, 08 Jan 2022 16:46:44 GMT

just to let you know that the green is steady now and how can I send you a picture? The link option doesn’t allow me to do so.