cancel
Showing results forย 
Search instead forย 
Did you mean:ย 

AC Hard start additions

popeyemth
Explorer
Explorer
Any new developments (in the last couple years) to the problem of starting/running a Dometic 13500 AC unit with a generator?
Thanks,Mike
"wine is a constant proof that God loves us, and loves to see us happy" ben franklin
22 REPLIES 22

ktmrfs
Explorer
Explorer
jjrbus wrote:
Rumor has it that some of the new roof air have a hard start installed at the factory. If they are no one is advertising it!

I got some bad info on the net then experimented a bit. I run an 8000 btu window unit with a Honda 2000, added a hard start an run the Honda in ECO mode!

I would have installed a mini split years ago but do not have room for the inside unit.


a lot of the "hard starts" installed at the factory are the same as what is in the over the counter AC units, a start cap for the compressor. Coleman and dometic sell OEM units w/o any start cap for the compressor. grunt grunt.

If the AC already has a start cap, a "hard start" cap may help some, but likely not much. Even with a hard start cap installed Locked rotor amps is still in the 50A range, well beyond what most 2000VA or so generators can supply for enough time to get the motor running enough to get the back EMF up to the point that the running amps are in the 15A range.

I graphed the start current with a micro air on My Coleman Mach III. PEAK start current is 20A for < 1 second, well within the capability of most 2000VA generators, even in eco mode. It took 3 or 4 of the "start learning cycles" that are called out to get their. Initially peak starting current was 45A w/o the micro air.
2011 Keystone Outback 295RE
2004 14' bikehauler with full living quarters
2015.5 Denali 4x4 CC/SB Duramax/Allison
2004.5 Silverado 4x4 CC/SB Duramax/Allison passed on to our Son!

3_tons
Explorer
Explorer
Another well founded internet rumor??

3 tons

2oldman
Explorer
Explorer
good one
"If I'm wearing long pants, I'm too far north" - 2oldman

jjrbus
Explorer
Explorer
Rumor has it that some of the new roof air have a hard start installed at the factory. If they are no one is advertising it!

I got some bad info on the net then experimented a bit. I run an 8000 btu window unit with a Honda 2000, added a hard start an run the Honda in ECO mode!

I would have installed a mini split years ago but do not have room for the inside unit.

ktmrfs
Explorer
Explorer
vermilye wrote:
I don't believe they are within the last two years, but the Micro Air Easy Start is a great solution.

Micro Air Easy Start


yup easy start. The only downside is at high altitude (>3500ft or so) a honda 2000 will run out of umph and shut down. A honda 2200 will run a coleman mach III or dometic at 7,000ft+ based on our experience.
2011 Keystone Outback 295RE
2004 14' bikehauler with full living quarters
2015.5 Denali 4x4 CC/SB Duramax/Allison
2004.5 Silverado 4x4 CC/SB Duramax/Allison passed on to our Son!

2oldman
Explorer
Explorer
Get more generator.
"If I'm wearing long pants, I'm too far north" - 2oldman

Sandia_Man
Explorer II
Explorer II
I don't know of any new developments if indicating 2K watt gennies, we have never had any issues to speak of since we use a 3K watt genny at a minimum for running our RV AC unit, no problems even at higher elevations.

vermilye
Explorer
Explorer
I don't believe they are within the last two years, but the Micro Air Easy Start is a great solution.

Micro Air Easy Start