Nest thermostat doesnt activate the heat

[Dech]

I recently installed the nest thermostat and all the wireds are connected properly but it doesn't activate the heat when I change the temperature. I also installed the power connector for the c wire

Wiring shows connected to w(p) -r

Voltage shows 31.xx

Power connector detected.

The power connector is connected as per the wiring behind the thermostat

[saltyegg]

I’m having the same issue

[Jake]

Hey all,

Sorry for the late reply. I wanted to follow up and ensure you are good to go. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further. 

Best regards,
Jake

[NatD]

Nest 3rd gen, added C-wire. Everything looks right on the display, but no heat. Shorting W to Rh actives heat. 3-zone system using Taco 571 valves. Everything works with a Honeywell TH6110D. Another zone works just fine with a Nest thermostat E on two wires. I tried using a relay (RIBU1C) between W and C but the contact between Rh and the zone valve never closes. Software issue suspected?

[jammy1954]

Hi @NatD : Did you ever get the Nest to work with the Taco 571 zone valve? I am about to try installing a Nest 2020 thermostat (mirror face) on a heat-only zone that is controlled by a 571. I have R, C & W wires. 

On another forum, a user claimed that an isolation relay would be required between the Next and the 571 because the 571 will intermittently open the R-W circuit to prevent the heating element from overheating the wax in its first stage. 
I'm curious if you found a different solution.