Hello my nest says I have an error code 257. I have a red, green, white,
and blue wire for my system. The old thermostat had a spot for the blue
wire. I have it in the OB slot. Does it need to be moved to the C slot?
So I managed to fix the problem. I had to go into the Google Home app
and change what the blue wire was from OB to C and that fixed the
problem. Then update wiring and bam problem solved. Thanks for the reply
tho.
