I have a 4 button Duo-Therm thermostat. It will no longer control the rear unit...no zone 1 or zone 2 at the bottom of the LCD. I have cleaned the switches checked the board for solder trace irregularities (burns). All buttons function normally and control the front AC, heat, fan, temp, etc flawlessly but it is as if the rear AC does not exist. I have tried the reset proceedure spelled out by Mr. Frerichs but no joy. I have unplugged and replugged the "telephone" jacks at both ends, wiggled all connections and of course tried mild (ok...moderate) concussive persuasion to no avail. Everything was working perfectly a month ago when we pulled her out of winter hibernation for a short shake down cruise. Has been plugged in to shore power all winter and ever since the short cruise. Did some searching here but did not find the exact issue. Any and all thoughts would be much appreciated.
Mike
william hendrix - Products (http://www.williamhendrix.com/Products.html)
Thanks Jim. I may have a wire chewing guest. I will eradicate with extreme prejudice.
Why not update your system with new boards and new 5 button tstat? It will permantly end the 2-button dance required with the 4-button tstat and prevent accidently turning system off when trying to change zone.
I finally got a chance to work this issue. As I suspected a mouse had chewed through the comm wires leading from the front to the rear AC. Thanks Jim C. For turning me on to William Hendrix website. A little solder and heat shrink and I'm back in business. Rear air working great. Any ideas on how to get the comm wire from front to back units? As I said it was chewed in two so no chance of attaching a pull wire during removal. I purchased some 3/32" cable and tried to run through the RH vent, but so far only aggravation.
Thanks,
Mike
Is the area confined that you want the wire to go through? If so air and dental floss.
Good thought, but no such luck.