3 wires red white and blue from Honeywell need help

[Jkyle]

In sun valley.   Have a Honeywell thermostat and removed it.   Have three wires red white and blue that control my furnace and AC.   The Honeywell was labeled 1,2,3 and I thought this would be easy.   But we can’t seem to get the AC to even show up on the nest.   Red we went Rh, white we went W1 and blue we just put in B……then tried blue in rc…… need help

[AxelD]

Hi Jkyle,

Thanks for posting in the Community! Sorry to hear that your Nest Thermostat isn’t turning on your AC. No worries, help is here! I’d like to ask some questions to gather more information:

1. Can I get a photo of your previous and current wiring configuration?
2. What kind of system do you have? Conventional or Heat Pump
3. Have you tried connecting the blue wire to C in the Nest Thermostat?

Keep me posted.

Regards,
Axel.