Community Forums

jlyon69 · 06-17-2011, 12:05 PM

Recently bought a '99 Class A with 2 ACs (ducted). The Duo Therm thermostat has been upgraded to the newer 5 button model a year or two ago and all worked well. After sitting for a month, neither ACs or fans will work, it also is not seeing the furnace. I've reset the thermostat to "scan" the system and now it only shows "EE".... no ACs, no furnace.

I've checked the DIP switches on the ACs and plugged/unplugged all the data cables I could find (thermostat and both ACs). I've been unable to locate or identify any data cable going to the furnace....any ideas?

I'm thinking my next step is to get a known good data cable and jump each segment to check it. I understand these data cables have the same number of wires and the same jacks as a phone line, but are wired differently. Anyone know how these can be cross wired to work or where to find new data cables?

Am I on the right track or should I be doing something different?

Mike Canter · 06-17-2011, 03:05 PM

Lets review your reseting of the thermostats. You had AC power applied to the MH, you turned the power switch off on the bottom of the thermostat and you then held BOTH the MODE and the ZONE buttons in at the same time while turning the switch on the bottom back on then counted to two and released the two buttons?

jlyon69 · 06-17-2011, 03:57 PM

Correct. While holding for 2-3 seconds FF was displayed. When released, EE was displayed.

jlyon69 · 06-18-2011, 07:42 AM

Problem still isn't fixed but, I found this Bulletin from Dometic which should assist greatly in resolving the problem. Is there a better place to post this (I'm new here) to better help others with similar problems?

http://bryantrv.com/docs2/docs/ccc5.pdf

RV Wizard · 06-19-2011, 03:10 AM

Quote:

Originally Posted by jlyon69

Problem still isn't fixed but, I found this Bulletin from Dometic which should assist greatly in resolving the problem. Is there a better place to post this (I'm new here) to better help others with similar problems?

http://bryantrv.com/docs2/docs/ccc5.pdf

I have uploaded a pdf file of the Duotherm service manual in our "Files" forum. At the top of each forum page is the page path box. Under it is a box, (on my screen it is blue) with a list of website areas. Click on the "Files" and you will get a list of sections you can choose for different files.
If you are getting the EE error code, this mean there is a data communication problem. Check the back of the thermostat and all data cable connections of both air conditioner units. If you still have a problem then replacement of the connector on the data cable would be the next step. These connectors and tool to install can be purchased at home improvement stores, electronic part stores or online. Pay attention to the color of wires in relationship to the connector and install the new one to match. Good luck and keep us posted.