topic Re: No power on pin 2 and 3 on heatlink after hearing the relais click when thermostat requests heat in Nest Thermostats

No power on pin 2 and 3 on heatlink after hearing the relais click when thermostat requests heat

BertNest — Sat, 12 Oct 2024 11:57:21 GMT

Hello all,

The google support could not help.

I moved house and have reset my system to an on/off system for only heating (oil). This means it should give power or remove power on pin 2-3 on the heatlink depending if it's requested via the thermostat or not.

I do hear the heatlink click when it is enabled or disabled via the thermostat so the connection works fine.

But I only get 0 volts on pin 2-3 in both cases...

Did anybody have this before and hence any idea how to resolve this? The heatlink looks ok (hardware) but seems not to give power on the pins when it should.

What am I overlooking?

Thanks

Re: No power on pin 2 and 3 on heatlink after hearing the relais click when thermostat requests heat

luciaaa — Tue, 15 Oct 2024 19:04:52 GMT

Hi, @BertNest,

Thank you so much for reaching out to the community. I’m truly sorry you are not getting power on pins 2 and 3 on Heatlink after hearing the click. I’m happy to help you and find a solution!

To troubleshoot effectively, please provide me with the following information:

What type of Nest thermostat do you have?
Did the problem happen during installation or after installation? Was the thermostat installed by a Nest Pro or by a regular installer?
When did the inconvenience start?
Have you recently had service or maintenance on your electrical or heating system?
Did you experience any power outages? Is your home receiving power?
Have you attempted to turn on the boiler (heating) manually? Was the system turned on? If you haven’t tried, please refer to the following link for instructions: Manually control heating when Heat Link is disconnected.

Please let me know if the boiler activated only using manual mode, and please let me know if there is any error code.

Best regards,

Ana

Re: No power on pin 2 and 3 on heatlink after hearing the relais click when thermostat requests heat

BertNest — Thu, 17 Oct 2024 08:34:21 GMT

Hello Ana,

3rd generation,

It never worked, so I don't know when it happened, before I was using open term in the previous house. I installed it myself.

When pressing the button on the heatlink to manually start it, it also does not give power on the 2 pins...

The boiler is disabled as this is not connected but also does not give power in manual mode.

No error codes given...

thanks,

Bert

Re: No power on pin 2 and 3 on heatlink after hearing the relais click when thermostat requests heat

luciaaa — Thu, 17 Oct 2024 17:18:25 GMT

Hi, @BertNest,

Thank you so much for your prompt response. I’m truly sorry the inconvenience still persists. I’m happy to assist you further.

To further assist you, please provide me the following information:

Is there any LED light on the Heat Link? If so, what is the color?
Have you experienced any power outages recently? If so, did the power restore correctly?

This information will help to determine the best course of action.

Keep me posted.

Best regards,

Ana

Re: No power on pin 2 and 3 on heatlink after hearing the relais click when thermostat requests heat

BertNest — Fri, 18 Oct 2024 08:01:56 GMT

Hello,

LEDs are green, no power outages.

As said, connection between thermostat and heatlink is working fine.

Kind regards,

Bert

Re: No power on pin 2 and 3 on heatlink after hearing the relais click when thermostat requests heat

luciaaa — Fri, 18 Oct 2024 19:47:43 GMT

Hi, @BertNest,

Thank you so much for your response and for the extra information.

Certainly, this is not a normal situation since you are completely sure to check the 2-3 terminals, and this does not send the instruction to the heating to start. However, since your Heat Link is with a green light, you listen to the click when the thermostat tries on the heating, and there is no error code on your thermostat. I suggest you contact a Nest Pro technician or a technician of your choice to diagnose your situation. This is for your safety and to be completely sure about the reason for this problem. This help is probably necessary since the error might be located in the configuration of your boiler.

Please feel free to reply if you have any questions.

Best regards,

Ana