AC not working

[Mark Beavin]

When I got my coach neither AC worked. Penguin by Dometic. I cleaned the coils and replaced the start and run Capacitors on both units. One fired right up and blew cold. The other just the fan works. Tested for power at the compressor and no power. Is the switch  on the face plate bad? I have a parts break down but no switches are listed. Anyone know what my next step should be?  1996 Beaver Monterey.  No wall thermostat.

[David Greer]

Mark,

I have the same units but was lucky enough to only have to replace the run capacitors 2 years ago.  Search online Duo-Therm 10-19-00 for the .pdf service manual.  Page 39 gives the troubleshooting steps for the analog control box.  To paraphrase, disconnect the six pin connector from the control box to the a/c unit and check with a 115VAC incandescent bulb between pins 5 (white-common wire) and 1 (blue compressor wire).  Duo-Therm says if it lights up the circuit is being made and if a component is non-operational, the problem is the rooftop unit.  I'd first check that the service manual electrical connector diagram matches what you have; it matches my 1999 Penguin 600 series units.

Dave

1999 Contessa Naples 40'
CAT 3126B

[Mark Beavin]

 Thank You Dave for that link. Was able to check the compressor out and it was a ok. Turned out to be the rheostat was not sending a signal to turn on. Both airs are working fine now. I did find out that the super start capacitors was to much a load for the generator. It would make my generator surge on start up and kick the power off momentarily. Put the old ones in and all worked as it should. Former owners were told they need to replace both ac units. I was ready for that when I bought the coach but have a race car trailer of the same year and my ac always works. Love this forum.

[David Greer]

Great info Mark on the super start capacitors.  I'll stick with OEM...   My dual run capacitor is a 20/5 ufd per the Penguin parts list but I removed something different if I recall correctly.  Agreed this is a great forum.