|
12-30-2010, 05:40 AM
|
#1
|
Montana Fan
Join Date: Aug 2010
Location: Garland
Posts: 450
M.O.C. #10688
|
Just a phase I am going through (50 amp)
Our 3750FL came with factory installed dual A/C units (15K and 13.5K respectively). During the PDI we were told both units are wired onto the same 50 amp circuit and to only run one unit when on a 30 amp connection.
My question is our previous fifth-wheel had the bedroom unit (13.5K) wired on the second 50 amp phase (there are two 50 circuits on a 50 amp connection) and wondered if this is really an advantage, disadvantage, or simply a mistake? Since both units are ducted there seems no benefit to having them on the same circuit and it may actually cause overload issues in the summer when both units are running, the water heater is on electric, the refer is on electric and my dear bride kicks off the microwave.
If it makes any difference, they will be installing a 5500 watt generator in the unit in two weeks.
|
|
|
12-30-2010, 05:45 AM
|
#2
|
Montana Master
Join Date: Dec 2006
Location:
Posts: 2,376
M.O.C. #6575
|
Personally speaking, I would put the front unit on the other leg. Makes no sense to me to load one leg down when two are available. If you use an adapter for 30 to 50 amps, you'll still be have both units available, just not advisable to run them both at the same time.
|
|
|
12-30-2010, 05:50 AM
|
#3
|
Montana Master
Join Date: Jan 2005
Location: North Ridgeville
Posts: 20,229
M.O.C. #2839
|
We had our Front A/C added by the dealer and made sure it was on a different leg than the one in the rear.
|
|
|
12-30-2010, 06:04 AM
|
#4
|
Montana Master
Join Date: Apr 2009
Location: Murrieta
Posts: 5,816
M.O.C. #9257
|
Consider it lazy work on the wiring. They should have been on opposing legs. No matter how it's wired you still can't run both ACs with only 30 amps, but it has nothing to do with the wiring.
Having the separate phases just means you'll have less problems when on 50amp shore power, needing both ACs and needing to run the other elecrical stuff too. It's a matter of sharing the load.
|
|
|
12-30-2010, 06:57 AM
|
#5
|
Montana Master
Join Date: Oct 2006
Location: McKinney
Posts: 7,166
M.O.C. #6433
|
As long as they are on separate circuit breakers on the same 50 amp leg, there should be no problem. 50 amps should run both fine. It would have made more sense to me to wire one on each leg, but what do I know.
If the microwave, water heater, and other possible high amp devices are all wired on the other 50 amp leg, it would make some sense.
As far as running both ACs on a 30 amp hookup, it doesn't matter one way or the other. You will probably trip the pedastal breaker.
__________________
Bill & Patricia
Riley, our Golden
2007 3075RL (recently sold, currently without)
|
|
|
12-30-2010, 07:38 AM
|
#6
|
Montana Fan
Join Date: Aug 2006
Location: cottam
Posts: 318
M.O.C. #6133
|
just my thought. if the 50 amp is red ,black. white and ground. red and black are live wires. white being neutal.if you are hooked to 30 amp then only one of the two hots are being used. red or black.if one air is wired to one hot say black and the other air connected to the other hot say red.then only one air unit the run on 30 amp .if you wire them on the same hot red or black then you have the oppostion to run either air unit.but not both of them on 30 amp .50 no problem.
|
|
|
12-30-2010, 09:36 AM
|
#7
|
Montana Master
Join Date: Oct 2006
Location: McKinney
Posts: 7,166
M.O.C. #6433
|
thor - when you use an adapter to connect a 50 amp trailer to a 30 amp pedastal, the adapter jumpers both hot lines together so everything in the trailer operates normally, except for a limit on total power of course.
__________________
Bill & Patricia
Riley, our Golden
2007 3075RL (recently sold, currently without)
|
|
|
12-30-2010, 09:40 AM
|
#8
|
Montana Master
Join Date: Dec 2009
Location: Sebring
Posts: 3,659
M.O.C. #9969
|
Thor, I think you better put your thinking cap on. When using a 30 to 50 adapter the two hot leads are tied together in the adapter. If it were wired as you suggested, half the rig would be without AC power when plugged into 30 amps or less.
__________________
Michelle & Ann
2018 Chevy 3500HD High Country DRW 4X4 Crew Cab w/Duramax/Allison, Formally 2010 Montana 2955RL, Now Loaded 2016 SOB, Mor/ryde IS, Disc Brakes & Pin Box, Comfort Ride Hitch, Sailun 17.5 Tires.
|
|
|
12-30-2010, 10:27 AM
|
#9
|
Montana Fan
Join Date: Jul 2009
Location: Hamilton
Posts: 143
M.O.C. #9497
|
You may want to check how they have distributed loads on the 120 volt distribution panel. If they are evened out already, moving may not be required or even advisable. There are numerous web pages that will give you the approximate amperage draws of the various loads. Your two A/C's will draw about 30 (+/-5) amps running. The smaller about 14 and the larger 16. You can check the actual draw by looking at the tags on the units. They may also giving starting amps. When the compressor in an A/C cuts in it will draw significantly more amperage. This momentary extra draw is handled by time delay type breakers in the distribution panel that are usually specified at 20 amps.
|
|
|
12-30-2010, 10:50 AM
|
#10
|
Montana Master
Join Date: Dec 2007
Location: Kansas City, Missouri
Posts: 2,707
M.O.C. #7992
|
I understand what you were told during the PDI. Others responding to your post have made good references to how they could be wired. Have you actually verified both AC's are on the same 50 amp leg? One person’s terminology doesn't always mean the same as another person’s. Would be curious to what your verification reveals. Jim
__________________
2006 3000RK
2009 Ram 2500
|
|
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Threads |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|