AC Units Come and Go

by Jim Moore
(Greenville TX)

Question: I have a 2000 monarch with two ducted ac units. worked fine for years. now they will both quit at the same time and when they quit, i lose 12volt power to my venta hood and the two lights above my couch. I can wait an hour or two and go back and every thing works fine. it is getting more often now. I do not lose any 110 volt power when this happens. I have checked all fuses. does anyone know what I should look for now?

Robbie: You've provided very little info for me to work with, but from what you've said it sounds like you may have "Comfort Zone" thermostat on the wall and I would guess it only has 4 buttons on it.

You will need to upgrade your system to a 5 button thermostat and will involve replacement of each circuit board in the Roof AC units. Contact any Dometic Authorized Service Center to get more information.


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Robbie Warford, San Diego RV Repair

Hi, I'm Robbie. Welcome to!

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