We have a Nest E thermostat that shows us the E45 Error Code on occasion. This is the second time in the past 4 or 5 months.
Today I noticed our Nest was offline today at about 3:00 PM with the E45 error code & the Nest thermostat said we were offline. When that happens, the furnace fan keeps running and distributes cold basement air to the rest of the house. I saw a status update that revealed there was an occurrence of some sort last night at about 11:30 PM. I presume that's when we went offline. I began troubleshooting using the Nest troubleshooting Matrix to dig into the problem. As the troubleshooting steps failed to correct the status, I tried to reset the thermostat with the 10 second press and hold and got an immediate message that the battery of the thermostat is too low to proceed and must charge. I took it off the mount to hasten the process via outlet and have since learned that the battery will take about 7.5 hours to fully charge.
Is that true?
Can I expect to get access to the thermostat before that so I can continue trying to resolve the issue?
Why does the thermostat battery go dead every time this code E45 appear?
We paid a furnace guy over $600 last time this happened and he had no good answer as to why that first E195 code appeared. They searched and searched and searched for issues and finally replaced a wire as the system (coincidentally?) came back to life. I'm starting to suspect the the thermostat IS the issue.
So now after charging again over night, I put the Nest back on the base. The thing boots then says it has to shut down to recharge battery. So I took it off the base to recharge by cable, it immediately gives me a message to put back on the base. I'll put it back on the base and it tells me it needs to shut down to recharge.
The troubleshooter has been absolutely no help. I can't find a lick of information on the website and there have been no responses from any forum experts at all. Everyone else seems to be getting some attention however.
What is the recommended procedure at this point?
