Nest won't turn on the condenser

[MarkS2]

Nest has been working fine for years.  Now it won't turn on the condenser.

When cooling, it turns on the blower, but it will not short the Y connection to the R connection as it must in order for the condenser to turn on.  It displays a long cooling duration, like 'for the next 2 hours', which I don't normally see and which makes me think it is working as designed, and is for some reason deciding that it can't or shouldn't turn on the condenser.

If I manually short Y to R, the condenser does turn on.  When I remove the short, it turns off.

[MarkS2]

I have two Nest thermostats in my house.  They both work normally with the rear cooling unit and they both work in the same abnormal manner with the front unit.

[mejiacruz]

Hi @MarkS2 

I'm very sorry to hear about the trouble you're having with your Nest Thermostat turning on the condenser. To get a clearer picture of the situation, a photo of the Nest thermostat wiring, particularly the Y wire terminal, would be very helpful. This would allow me to see if the connection is secure and in the correct terminal.

All the best,

Josh