nest thermostat kept heat on

[Jb6616]

Nest learning thermostat will not turn heat off.  Its on farenheight, with new signal cable, new burner control unit.  Was set to 62 (outside temp. 25 - 30 f).  Had house up to 85 - 90 f.

[CoolingWizard]

@Jb6616 , please post a picture of the Nest Backplate with the wires attached.  You say a new thermostat cable was installed? Was it properly wired  by the contractor? Did he not test the system before departing your home? This sounds like the thermostat cable is not wired correctly now. 

AC Cooling Wizard

[Jb6616]

There are only two wires to the thermostat.  When originally installed it kept the temperature at 62.  After nine weeks the thermostat kept the heat on.

[CoolingWizard]

You need to check both ends of the thermostat cable to ensure that the two wires are terminated on the same lettered terminal as the thermostat.  

AC Cooling Wizard

[Jb6616]

Control unit on burner does not have identifying labels.  i have tried switching wires (2)

[Jb6616]

Why would thermostat work fine for 9 weeks then not turn off call for heat after that?

[CoolingWizard]

@Jb6616 , frankly I have no idea why it would behave in this way. Post a picture of the Furnace end of the thermostat cable.  

AC Cooling Wizard

[Jenelyn_O]

Hi there,

Thanks for reaching out. I'm sorry for the delay. Just to confirm, is your heating system will only stop when you turn off your thermostat mode and power? Please provide your thermostat power readout by going to settings and technical info.

I appreciate your help, @CoolingWizard.

Best,

Jenelyn

[EmersonB]

Hi everyone,

@Jb6616, I'm dropping by to ensure that everything is covered here. How's it going with your Nest Thermostat? Were you able to read the information and check the link that Jenelyn has shared? In case you have an update, you know where to find us.

I appreciate the help, Jenelyn and CoolingWizard.

Regards,
Emerson

[EmersonB]

Hey Jb6616,

Just one final check in here since activity has slowed down. We'll be locking the thread in the next 24 hours, but if you still need help, we would be happy to keep it open. If there's more we can do, just let us know.

Thanks,
Emerson