Forum Discussion

Stevec4s's avatar
Stevec4s
Explorer
Aug 06, 2020

Dreaded EE code

Hello all,

I need help with Ac. I have the 5 button duotherm. I have replaced the thermostat, one communication cable that was bad and the control board. Actually two of them. I have tested both communication cables the one going to front ac and the one to the back ac. Both are good and wired correctly. My units are the older penguin heat pumps. What am I missing turn thermostat off press the two buttons get the FF then release and get EE.
Have checked the 12v and 110v and all good. All duotherm said in email is you have communication error. I Know that but why? Help!

Thanks in advanced!
  • Stevec4s wrote:
    I will have to look closer. It looked like my communication Cable plugs directly to board without union.


    Is your Control board in a 8 by 8 inch Galvanized Box? Right in front of the Evaporator? This is important. Depending on the AGE of the penguin determines WHERE the Control board is located. If the control board is MOUNTED and accessed from the TOP of the RV under a flat metal plate that has 2 screws, you will see 2 black 4 wire Com cables connected to the Control Board. THOSE black cables(about 18 inches long) go into the Evap area and have those splice unions that connect to the cable from the wall tstat and then go from the other to the rear Zone 2. ALWAYS disconnect the Rear Zone 2 from the Rear control board at those splice connectors. As I stated, you need to make another Com cable 2 or 3 feet long and do on top and connect the wall tstat direct to Zone 1 Control board with the other Com cables disconnected. Doug
  • I will have to look closer. It looked like my communication Cable plugs directly to board without union.
  • Thanks for the reply Doug! Both board's are new and the same result as with the old boards. I take it the unions you are talking about are the p1 and p2 jacks on the control board? If so they are new and clean. You do mention beige in color mine are black. I did make my own cables and checked the wiring 4 times and it is correct to the wiring diagram. Also checked with a cable tester and all reads good. I'm stumped. I have a 2005 Monaco Diplomat.
  • 1. You do NOT need 120 volts for the system to work. Just 12 volts. You have that as you get the EE error
    2. YES, COM problem. The FIRST thing you do is connect a GOOD Com Cable to Zone one AT the UPPER board and the wall tstst to the test cable. Since you have Older penguins, the most common problem of EE error is corroded(rust) connections. EACH Penguin has a 2 beige JUMP(union) Phone type junctions from the Control boards. THOSE unions are where the rust forms. They are usually located right in front of the evaporator in the return air space and that air is moist hence they get corroded after years of use. Access those 4 (2 on front ac and 2 on rear AC), and you will probably find your problem.
    3. LAST, I assume you built your new COM cables correctly? They are NOT Phone cables. COM cables are wired in reverse, if you used PHONE prebuilt cables that is your problem. Doug

About Technical Issues

Having RV issues? Connect with others who have been in your shoes.24,210 PostsLatest Activity: Mar 04, 2025