13,500 A/C and "hard start" capacitors and genny's

otrfun wrote:

NinerBikes wrote:
One Honda Eu2000i running 13.5k BTU AC, if it starts it at all, will have a pretty annoying "bark" to the pitch of the exhaust tone, the motor is laboring mighty hard. And it's not good for the longevity of the single motor.

Better to split the load with a paired set of Eu2000i's, or get an Eu3000i instead.

In eco mode, the Eu3000i is the quietest unit, by far, of any gen set I have camped around. It is noticeable.

You're making the assumption that ALL 13.5k BTU a/c units have the same power requirements. They don't.

very good point. the coleman MachIII version that is low current is very close to the same inrush and running current as my coleman power cub 9000BTU unit on my 2nd trailer. the honda 2000 will easily start and run the polar cub even in eco mode under almost all conditions. the only time I need to turn off eco mode is at altitudes above about 6,000ft on a day in the 90's. not real common.

On the other hand it's ALMOST enough to start the regular coleman Mach III I have. not reliably, if it could hang on for another second it would probably start it.

Remember "barely adequate" and "almost adequate" are NOT the same!! unfortunetly for the standard coleman machIII the honda 2000 IMHO is in the "almost adequate" category for that AC unit

NinerBikes wrote:
One Honda Eu2000i running 13.5k BTU AC, if it starts it at all, will have a pretty annoying "bark" to the pitch of the exhaust tone, the motor is laboring mighty hard. And it's not good for the longevity of the single motor.

Better to split the load with a paired set of Eu2000i's, or get an Eu3000i instead.

In eco mode, the Eu3000i is the quietest unit, by far, of any gen set I have camped around. It is noticeable.

You're making the assumption that ALL 13.5k BTU a/c units have the same power requirements. They don't.

One Honda Eu2000i running 13.5k BTU AC, if it starts it at all, will have a pretty annoying "bark" to the pitch of the exhaust tone, the motor is laboring mighty hard. And it's not good for the longevity of the single motor.

Better to split the load with a paired set of Eu2000i's, or get an Eu3000i instead.

In eco mode, the Eu3000i is the quietest unit, by far, of any gen set I have camped around. It is noticeable.

Whenever the topic of trying to power a 13.5k BTU a/c with a generator comes up, it seems the discussion/solution usually assumes the air conditioner is a static, unchangeable part of the equation.

FWIW, a Honda EU2000i produces enough continuous current to "run" nearly every 13.5k BTU a/c (10-14a). As has been discussed numerous times, it's typically the excessive startup compressor (inrush) current that's the deal breaker for the EU2000i.

LRA (compressor inrush current) for an OEM 13.5k BTU a/c is typically 58-63a. Since a Honda EU2000i can only reliably and consistently produce 50a (Eco mode on) and 54a (Eco mode off) of inrush current, it's easy to see why it has problems starting many of these OEM units.

There is a 13.5k BTU a/c unit with an LRA as low as 48-50a and a continuous current rating of 10-11a (Coleman Mach 3 PS 9xx series, NOT the older 8xx series). I've seen one (1) Honda EU2000i run one of these Coleman units with the Eco mode on (yes, on) in a 105+ degree desert environment for 48 hours straight. Not saying this combination can be guaranteed to work in every situation, but it is a potential option that some may want to consider. I've seen these Coleman Mach 3 PS 9xx series roof (only) units on sale for as low as $499. Typically they cost ~$700.

In any case, a bit cheaper than $900-$1000 for a 2nd EU2000i. Plus, consider 1) the fuel savings, and 2) the much lower sound level of running one EU2000i vs. two.

Thanks to everybody that responded!

I did a real good look at generator in the class C. To much work to swap it around even if I only had to do it once a year.

And I never even thought about how the temps would effect the starting process of A/C.

Lots of good knowledge on this forum.

Thanks again.

Path1 with a hybrid inverter you could do it--but only when it is not very hot. I've monitored the 13500 on the RV. Wattage goes from 1200 up to 1900 as the day gets hotter. Elevation where these measurements were made is 585 meters (1920 feet).

my experience is that it will usually start a coleman if:

1) temps are no higher than the low 80's
2) your near sea level
3) AC unit is shaded
4) EVERYTHING else in the trailer, including the converter (charger) is OFF
5) ECO throttle is OFF

in other words, it will when you really don't need the AC.

go above about 90F, go much above sea level, or try to run anything else, and most of the time you'll Be SOL.


For reliable consistent operation you need a parallel kit.

The Onan in the "C" is not like a Yamaha or Honda... it will need to have a battery, fuel lines, and power lugs. You could do this, but dropping the genset, hooking it up to a gasoline tank, wiring it up, then undoing all that and sticking it back under the "C" is a lot of work.

I would consider a 3100 watt Champion inverter generator as another idea.

OK thanks folks. Good info. I was thinking I could maybe save some $$$ on only buying one generator for trailer. Going back to drawing board.

My plan "B"

Plan B (option 1)... Forget about A/C. Only a couple of times have we really needed A/C. But when we do, we really do.

Plan "B" (option 2)... The generator in our class C is 174 pounds (Onan 4,000). Once a year move it out of class c to the bed of pick up and use it in "wife's trailer", we part time maybe 4 or 5 months of year down south in trailer. Rest of the year we use our older Majestic for around northwest. I do have pulley set up in the bed of pick up to get heavy stuff in and out. But I don't know of any easy, quick way get the generator back into its slot in the class C with out a major hassle. And I do know gravity works real good one way, and the other way is a pain.

What's the use of micro-matching this stuff when you are going to have a sizable hotel burden to begin with? An air-cooled engine that is operated at capacity will live about 30% as long as one that is loafing. You cannot imagine what intense heat does to everything from metal, to lubricant to generator accessories.