SCS AIR CONDITIONING

[Lyle Johnson]

2000 Beaver Marquis
cat C12 425hp
oK...read as many blogs that I could find about the SCS air unit.
WOW!  I think I have a problem.
First of all I purchased the coach in Bend, Or. 3 years ago with "zero" hours on the air unit just installed. Since then
have used it about twenty hrs. total. I turned on the air unit a couple of weeks back and (to shorten the
Story) the first leg reads normal for amps but the second goes off the 50 amp to high range. Am I looking at a no. two
Compressor failure?  I am still looking for that elusive air filter too but will keep on looking.
I have read Mr. Farris's blog about taking the unit out and believe I can do that if needed.
Any help in this regard would be welcome.
Thank you
Lyle

[Steve Huber Co-Admin]

Lyle,
Does the primary compressor run and cool if you have fan set to Low? If so, it's OK. Then you should be reading normal amps on AC1 and 0 amps on AC 2. If you see high amperage on AC 2 with fan on low, I would suspect a bad control board.  When switching fan to High 2nd compressor should come on if needed to cool coach. Then you should see approx equal amps on both circuits. If you then see high amps, I'd suspect compressor (but I'm not an AC guy).
If mine, I would take it to shop (that you trust) and have them check out control board. If bad, and they replace it, get the bad board from them. Flight Systems will repair for $85. Then you have spare for future trouble shooting, etc.
Return air filter is located in 2nd large bay on back (dvrs side) wall near inverter. Carpeted panel is held on by a couple of screws. I needed to put in 2 filters, side by side to filll opening. Suffering from CRS so not sure of filter size but got at Home Depot. See pic.
Good Luck, Steve

[Lyle Johnson]

Ok...found the filters...always wondered what was behind that door...
When testing as you recommend should I be hooked up to 50 amp or run generator?  I am a this time hooked up to 30 amp.

[Lyle Johnson]

Anyway, I ran the unit on low and only had a 4amp draw...none on second leg.  Went to high setting for several minutes and no amp draw.  70 degrees in coach...set the thermostat to 60 ...no change.  Blows cool on low setting.  
Generator running.  Also on high setting did not notice fan speed change.

[Steve Huber Co-Admin]

Lyle,
If your unit is like mine it may take a few minutes for the 2nd compressor to kick on when fan is on High and thermostat is set to low temp. In any case if you only get the super high currency draw when 2nd unit is on, I'd suspect compressor. Maybe someone on forum with more SCS experience has more info??
Steve

[Lyle Johnson]

Steve,

I tried the high setting for about 15 minutes...nothing changed. It is acting different than before. I will try again tomorrow.
Thanks for the reply,
Lyle

[Gerald Farris]

Lyle,
Call me and I will walk you through diagnosing your A/C problem.

Gerald

[Lyle Johnson]

Gerald,

Thank you for all your help on the telephone on the way to N. Mex.,...
I enjoyed the conversation and wanted to let you know how much I appreciated the time you took to
explain some of the things I needed to know.  

And then Steve...thank you for the quick response and the picture....it was much appreciated .
Lyle