So, I just got one to replace the Airxcel labeled one that I thought was bad...and I had the same problem....well, after looking at it closer, it comes with a base plate screwed to it...I took that off and it fits in the original base plate mount. sure
didn't look like a base plate was on it when I took it out the box.....
On a side note.... the new thermostat didn't cure the problem, but created another one....
... and does not have all the features of the previous one, specifically the high/low fan when on the electric heat setting like the original thermostat had...
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S&T
2019 Entegra Insignia 37MB
2022 JEEP Wrangler 4xe (chase and touring vehicle)
(2019 NP 383FKWS)
(2019 RAM 3500 DRW Big Horn)