Starting about four weeks ago, on some days my Nest generates an e74 error. At first I thought it was due to an overflow (I had that once 2 yrs ago) but it wasn't that. e74 usually occurs between noon-3pm and resolves in the evening.
Today is the 6th time it has happened (hasn't resolved yet). It occured when I switched from the AC running to ECO. After the 4th time, I brought my HVAC guy out who went into the attic and checked everything with the furnace and said it was all fine, and probably the thermostat.
I currently have the unit off its plate and am charging it to see if that makes any difference (it hasn't other times). If it comes back tonight as it has the other times, I will try a factory reset. If not, I am ordering a different brand of thermostat. If it was an electric company metering stunt, it would have happened on the hottest days of the year in late June. It was 101 on July 3, and it ran fine. I have had the thermostat for almost three years.
Any other suggestions?
