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Pawjam3 · 07-13-2013, 04:26 PM

We have a 30 ft. Coachman Chapparal 5th wheel. Does anyone know how much wattage the A.C. pulls? I have an emergency generator that can handle 1650 watts. Thanks! Jim from St. Louis

Ray,IN · 07-13-2013, 04:37 PM

Quote:

Originally Posted by Pawjam3

We have a 30 ft. Coachman Chapparal 5th wheel. Does anyone know how much wattage the A.C. pulls? I have an emergency generator that can handle 1650 watts. Thanks! Jim from St. Louis

I've never seen that small a genset with a 30A receptacle, a 15A receptacle will likely overheat if you genset could manage to power your A/C unit.
Your air conditioner will have a data plate showing the starting amperes draw and running amperes draw. Olders units could draw around 13A while running, newer units around 9A running. Amps X volts = watts, so 13 X 120 = 1,560 watts.
You must figure in your converter draw that is re-charging the house batteries, and anything else operating on AC voltage. Your genset might barely power your A/C running, but startup draw will be too much for your genset to handle.

CampDaven · 07-13-2013, 04:44 PM

The formula is P=IxE.
Watts = current x voltage

a 13,500 btu unit draws about 14 amps, so 120V x 15A = 1680 watts.
This is just my guess.

So, it might run if that is the only draw (nothing else plugged in or running) but I doubt it could handle the surge on AC start up.

Others may chime in on this.

hjsdds · 07-13-2013, 05:59 PM

Quote:

Originally Posted by CampDaven

The formula is P=IxE.
Watts = current x voltage

a 13,500 btu unit draws about 14 amps, so 120V x 15A = 1680 watts.
This is just my guess.

So, it might run if that is the only draw (nothing else plugged in or running) but I doubt it could handle the surge on AC start up.

Others may chime in on this.

Right on, since 1781 when Georg Ohm got zapped by electricity and decided to figure it out. All appliances have a sticker telling you how much current they take, so use the formula above and add everything running to see if the genset is up to the task. Probably not.

hjs

jesilvas · 07-13-2013, 06:03 PM

AC could draw 13-14A depending on fan speed, ambient temp, etc. Then converter can pull quite a bit, depending on lights and batt. condition. Say 5A avg. Then refr heating element is 2.8 or so, so 3A.
22A. 120VAC. 2640W.

wa8yxm · 07-14-2013, 07:13 AM

Air Conditoners vary and you can't tell by the BTU's. You can tell by finding the label on the upper unit and reading it, that is the only way.. I have two DIFFERENT A/Cs on my Motor home the OEM Carrier Air V is 13,500 BTU draws 13.5 amps running, the new Advent Air 15,000 btu job draws 13.5 Amps running, 13.5 times 120 is the volt-amp rating. (Too early in am for me to do math).

This is typical of many a/c's but some draw more, some less.

Worry about Volt-amps, not watts, by the way. Though the better the A/C. the less the difference.

menoble · 07-14-2013, 07:33 AM

You'll need more generator. 1650 is enough to charge your batteries and run your fan, the start and continuous run load on your A/C compressor will take another 2000 or so.