Hi Rich
It was great to meet you guys yesterday.
I found something on the web that says E1 is a loss in communication from the control panel to the unit.
So first thing I'd try is just check the plug in the back of the thermostat.
I don't think it's going to be there. My thought is it's going to be the cheap connection up in the unit. You'll have to remove the shroud/cover and the take the screws out of the front cover plate. In there you'll find a cheap phone line to phone line connector that gets moisture inside then starts failing. I think some have sprayed a cleaner in there and put Dielectric grease in it to prevent it from happening again.
That's where I would start if it were me.
I found my pictures
Jerrod
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