Basement A/C

[David 70]

Will do sarge

[Starsekr]

[QUOTE=David 70;5868095]2000 Adventurer 32v, P32, 7.4l
Is there any way to disable the second ac compressor on these units?

I can only give you advice as I see it through my 2005 Adventurer 37B . Easiest is flip off the 20 amp breaker on the gen set. 1st AC side & fan should be on the 30 amp breaker (Phase 1) and the 2nd AC compressor on the 20 Amp (Phase 2) breaker. or/ Remove the power from the 2nd AC compressor at the AC unit. Lift the cover over the AC, (With all power off) remover the cover plate on the corner of the AC that exposes the control board and start capacitors. Clip a volt meter to one AC power input line and the other to the AC ground. Apply gen power to the coach. You are trying to determine which AC phase powers the 2nd compressor. Flip the breakers on the Gen set as above. When you find the power wire that powers the 2nd compressor, disconnect it and tape it up very well with two layers of Scotch 33 electrical tape.

[joemcgin]

I know it's been a while since you last posted. How have you made out since then? I have the 6535-871 model and have no issues with turning off the AC Breaker on position 3 in the breaker box by the stairs to turn off my 2nd compressor.

I added 2 Supco SPP6 Hard Start kits to my AC Control unit in June. About $14 each on Amazon and will be looking to replace all of the original capacitors as soon as I can identify which ones to buy.

[David 70]

Yes it has been a while since I posted. I haven't had time to investigate any further. The ac's keep the coach cool on shore power or with the Onan. I am keeping busy with several tractor shows at present I just spent 10 days working at one and need to head for another in 7 days. My house batteries died last week all of a sudden so I had to replace them today. We have a golf cart with us most of the time and the starter/generator acted up on it so I also had to have brushes put in it. I need to get it to the electric motor repair guy and him check the capacitors but that might not happen until I get back but then it is harvest time here so I will need to help with that. I will report later if I find something , hopefully this year yet. Does your load shedder go right to 50 amps when you turn off one of your breakers. Mine is a 30 amp service but if yours is 50 amp I guess it wouldn't make any difference.

[joemcgin]

Hi David. My Power Center stays at 30 amps when I shut off Breaker 3. When yours goes to 50 amps on the display can you use the selector button to set it back to 30 amps?

[David 70]

No, I have tried that and it won't come off of 50.

[Brob]

Originally Posted by David 70

Can a person add a soft start to these units? If so, any recommendations?

I have successfully installed the 5-2-1 soft start on a couple of RV units. They do make a difference.

[AFChap]

I am under the impression that when on 30 amp shore power just the #1 compressor runs. Correct?

NO. BOTH compressors will run on 30a. After the start-up surge, #1 will be pulling apx 17a, and with both running they will pull apx 24a.

[joemcgin]

Agreed. Even though the manual says only one will run on 30A Shore Power, both of mine do run on 30A with the 30 second delay.

[BCam]

Originally Posted by joemcgin

Agreed. Even though the manual says only one will run on 30A Shore Power, both of mine do run on 30A with the 30 second delay.

A couple of years ago I was considering a replacement unit but was concerned that the specs required 50A. I contacted the vendor and they confirmed both compressors would run on 30A, which is true of my original 2002 unit.

Although both will run on 30A, you're limited as to what else you can run before your power management system starts shutting things down.

I think the manufacturer specifies 50A to avoid complaints.

[David 70]

Thanks for that info. I was going by what the owner's manual says so far as just one compressor running. on shore power. I have just 30 amp power so I was thinking the manual was right but always wondered about it. I have a show next weekend and it doesn't look like I will need ac up here. I need to get the capacitors checked when I get back.

[Brob]

In my 5th wheel there is a switch (looks like a residential light switch) that says 30A on the bottom and 50A on the top. When on 30A it cuts power from one leg of the basement A/C unit.

[Starsekr]

I'll just mention that when it is really hot (100+) that the starting and running currents go up in an A/C. Higher temperature causes the pressure of the refridgerant to go up. This causes the comnpressor to work harder and draw more current. A 14 Amp compressor draw at 90 degress will go up to 17-18 Amps in the desert, and of course starting amps will be even more.
That said, Amp ratings are averages. Most circuit breakers are +/- 10%, but thermal or thermal magnetic breakers need to be derated for high enviromental temperatures too. The normal spec temp is 40 deg C (104deg F), but boxes on a post in the summer sun can get to 150 F, easily. Or think how hot the breakers must get inside your generator cabinet.
One thing I've done when I have had touchy power is flip off phase two at the breaker box, wait until the 1st stage of the compressor settles down, then turn phase two back on to start the second stage. Since this is in Nevada in the summer, the compressors never turn off for the whole of my stay, and I run the water heater/ refridge on propane and don't use the microwave unless I shut the A/C off for a few minutes. Load management.

[bobpie231]

Originally Posted by NeilV

The simple answer is to turn off the breaker in the main panel for the Second AC compressor. The factory setup when running on the Onan built into the coach has one compressor on the generators 30 amp built in circuit breaker and the other compressor on the generators 20 amp built in circuit breaker.

The 3,700 watt Westinghouse is a little under powered to run both AC compressors however you may need to check the condition of the capacitors and the solid state devices on top of them for the Air Conditioners compressors. With the constant low voltage found at many campgrounds the Capacitors and their Solid State Modules do take a beating and when either the Capacitor or Solid State Module fails they should be replaced as a matched set. When the Solid State Module fails it will present like a locked compressor despite the capacitor testing out as good.

The capacitors are accessed by opening the hinged grating covering the basement air unit and will be inside the black control panel found to one side behind the grating. The last time I replaced those capacitors and the solid state devices the matched set of 2 capacitors and 2 solid state devices was a little over $50.

I need to replace mine Neil, can I asked where you bought them at so I can get them also? thanks
Bob Stefanow @ bobpie231@gmail.com