Basement Air Conditioner Probs - Heat Wave Coming!

[Mike and Cathy Cleghorn]

PLEASE HELP!

The basement air in our '02 Marquis has a couple of issues. We're in Lake Havasu City, AZ and the upcoming forecast is for several days of 100º-105º weather.

1st issue: When I turn the thermostat on (high/60degrees), about 20% of the time the fans blow but the compressors don't turn on until I go outside and touch the AC access panel-door fastener screw or I remove the panel-door and touch the relays. The condensers then turn on and the system cools.

2nd issue: In the last few days, when the AC in on and cooling. the unit seems to make a sound of a "pause or delay". I've noticed that when this happens the Silverleaf monitor panel shows that the "AC Current Leg 1" reading changes from about 13 amps to 37amps to 49amps to High (red light), then immediately returns to 13amps. The cycle is repeating every 15 to 20 seconds.

Any ideas about my two issues?

THANKS - MIKE CLEGHORN (503-307-5783)

[Edward Buker]

Mike,

The problems may be related. If you get false starts with just the fan running, then it is likely that something electrical is preventing the start up. From what you say I would suspect a bad relay contact, a bad relay socket, or a bad connection to the relay or some other aspect of the electrical control system. I'm not familiar with your system but as a trouble shooting technique you can use a pencil eraser or typwriter eraser as an implement to very locally touch electrical connections, relays, etc. to see if you can find what is causing the problem. If you can get hold of replacement relays and they plug in I would change them to rule them out. The contacts are ten years old anyway.

On problem two if you momentarily lose contact and the compressor stops for just a second, and then sufficient contact is remade, then the compressor motor is trying to start the compressor while there is a lot of high side pressure built up working against it. There usually is a delay circuit that sets a specific time that allows the low and high side pressure to equalize therefor lowering the high side  pressure and starting curent. Your case may be too quick to enable the delay circuit.

There is also a possibility of the beginning of a compressor fail causing a lock up that would induce a high current start. I would not go there until you can find the electrical gremlin and eliminate that. I think the repeated high current cycling that you are seeing is the system trying to start the compressor and either an electronic circuit or a thermal breaker is dropping power to save the motor/compressor and then trying again to restart. The repeatable timing would lead me to belive that a thermal breaker may be involved. This is a bit of a shot in the dark, hope it helps. There may be some other owners of these systems out there that have had this symptom before and can help.

Later Ed

[Bill Sprague]

Mike,

When we were doing the headlight video, Roy Mueller was telling me about a source for parts as well as successful repairs on other coaches with that system.  You might give him a call.  He may even still be in Havasu.  He was there when we were.  

It is supposed to be 95 there today!  There is an unused shade tree on lot 391 next to a babbling brook if repair is not successful.

[Mike and Cathy Cleghorn]

Thanks for the many replies, both on the Forum and via the phone.

1st issue: No change, but has not been an problem for several days.

2nd issue: The problem is related to the compressor, or the overload protector, or the capacitor, or the start assist on Circuit #1. So I've disconnected the control board plug that feeds all of the former, and now am running on the compressor, etc., on Circuit #2.

Even running with only one compressor, the coach is still cooling nicely, even at 95º here in Lake Havasu City. I'm not sure how things will be when we hit the new forecasts of 106º Saturday, and 107º Sunday, but we will see...if we haven't headed to Bend yet and Beaver Coach Sales for R&R on the AC unit, then on to Leavenworth (home).

Thanks especially to my many helpful Beaver friends Al Vormittag, Jim Gillis, Gary Wingerd, Gerald Farris, Ed Buker, Mike Humble, Roy Mueller, Joel Weiss, Bill Sprague, and Ken (Beaver Coach Sales). It's so great to have so many knowledgeable folks always willing to lend a hand.

See you down the road!

Mike