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kimanderson98642
06-20-2011, 04:50 PM
How big of a generator do I need to run my A/C Only for short periods of time on my 292RKS with roof vented system while dry camping. The 5th wheel is a 30 amp system and the paper work says that the A/C uses 15 amp. I don't know enough about generators but will a 2000 watt work.

mhs4771
06-20-2011, 05:57 PM
You will need at least 3000 watt or two 2000 watt connected together.

tcaggie
06-21-2011, 03:14 AM
He would need more than the 2000W to run everything... however, if nothing else is used, the 2000 should run just the AC. The 2000 should have almost 20 amps avail and the AC usually runs up to 15. Not an expert here so I could be overlooking something.

I plan on trying that here soon only my generator is only 1500W and that my be iffy at best.

LeeMedic
06-21-2011, 03:22 AM
He would need more than the 2000W to run everything... however, if nothing else is used, the 2000 should run just the AC. The 2000 should have almost 20 amps avail and the AC usually runs up to 15. Not an expert here so I could be overlooking something.

I plan on trying that here soon only my generator is only 1500W and that my be iffy at best.

I thinking a brown-out condition could harm electrical equipment. Be careful with this experiment.

JRTJH
06-21-2011, 05:31 PM
I posted a response to a question like this on another forum about 3 months ago, I'll try to summarize that post here. Very siimply, the way a generator works:

When you start a generator, the gasoline engine turns a generator stator through a magnetic field. That stator displaces electrons (negative energy particles) which flow toward the other side of the magnetic field. They are "captured" in wires in the stator and flow through the generator connections to the RV. The stator windings produce heat based on the flow of electrons. The more flow, the hotter the wires in the stator become. These wires are coated with varnish to insulate them from each other. When they get hot enough, the varnish breaks down. This causes the electrons to "short circuit" or take the short trip, thereby causing additional heat and more varnish breakdown.

Now, with a 2000 watt generator, at 120 volts, you can produce 16.666 Amps. This "should" run a 13,500 BTU AC. I say "should" because after the generator runs this load for a period of time, the varnish starts getting hotter and hotter. Add the converter and its 4 or 5 amps and you're right at the maximum generator output. Now, let the AC cycle off and then back on and you've heated the stator wire varnish to a point of melting, and some of the windings in the stator short out. Now, imagine that 2000 watt generator can only produce 1990 watts because of that varnish meltdown. The cycle starts again, the generator produces 1990 watts and when the AC cycles next time, more varnish melts and you produce 1975 watts.

Imagine this continuing over and over. How long will a 2000watt generator continue to provide enough power to run the AC ? Who knows, maybe a summer, maybe until you get to the Rockies and the gas engine can't turn the stator as well because of altitude power loss, maybe for part of the second season, but maybe, JUST MAYBE it'll work the first day, but won't work the second day of your camping trip and you have a brand new generator that is "burned up".

Don't run a generator on a load that is so close to the maximum, it'll work, but not consistently.

As many here have said, a 3500 watt generator (that's 29.166 Amps) or two 2000 watt generators in tandem will provide adequate power and protect the generators from heat buildup and keep you cool for years to come.

Hope this very simple analogy helps you understand that just because the generator says it will produce 16 amps and the AC says it runs on 15 amps doesn't mean it will provide power to keep it running.

ktmracer
06-21-2011, 05:43 PM
How big of a generator do I need to run my A/C Only for short periods of time on my 292RKS with roof vented system while dry camping. The 5th wheel is a 30 amp system and the paper work says that the A/C uses 15 amp. I don't know enough about generators but will a 2000 watt work.

here is my experience.

My Honda 2000 W generator will start and run the 13,500BTU A/C if:
1) it is less than about 85F outside
2) you are at or near sea level
3) you have a good hard start cap on the A/C (not on a OEM unit By the way)
4) you have NOTHING, repeat NOTHING else on when the A/C starts, that includes turning off the WFCO charger, and turn on nothing after it starts.
5) the generator eco mode is off


Now, how many times are you camping under ALL of the above conditions? For me not many, so it's a pair of honda's. Violate any of the above, especially (1) and (2), and the A/C won't start, the rotor will lock, the generator will overload and trip. (1) high temp, causes starting current to rise, (2) causes generator max output to drop. A/C needs 30A for up to 5 seconds to get started, well beyond most 2000VA generators.

Txoutback
06-21-2011, 06:37 PM
I run a Champion 3500/4000RV and am quite pleased with it. It's not the quietest unit in the CG and weighs in at about 100lbs but has been reliable for 4 years now and has a built in TT-30R for direct plug in without an adapter.

JRTJH
06-21-2011, 06:46 PM
I run a Champion 3500/4000RV and am quite pleased with it. It's not the quietest unit in the CG and weighs in at about 100lbs but has been reliable for 4 years now and has a built in TT-30R for direct plug in without an adapter.

Same generator I have. It's not super quiet, but reliable, powerful and gets the job done. Besides, they're on sale at Tractor Supply for $279. Can't beat that with a stick... LOL