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Generator won't start camper air conditioner

Willie_Jim
Explorer
Explorer
Year old Bullet camper, AC General Electric unit lists three model numbers, with a square the manufacturer was supposed to mark the appropriate square, but didn't. It draws 13.2 amps running load which agrees with the smallest model.
On house power it starts & runs fine. On the occasion I can get it started, it runs fine on the generator.
Generator is a new Generac GP3300I rated 2500 watts continuous & 3300 starting power (20.8 & 27.5 amps)

Hard start capacitor sets are available on line, but little information is given about installation or applications.

Any help would be appreciated.
17 REPLIES 17

valhalla360
Nomad II
Nomad II
Mike134 wrote:
AC units (any motor) will need to draw 6X running current for just an instant at startup. When plugged in at home or a campsite that is no problem getting that from the utility.
Problem comes in trying to do it from a generator.
Solution is the Mico air soft start. Don't waste $15 on a "hard start capacitor" those only help when connected to the utility power.

https://www.micro-air.com/products_groups_easystart_soft_starters_microair.cfm


Technically true but for the same reasons a 30amp shore power can handle it, a 3300w generator should be capable also.

Make sure everything else is turned off and the batteries are fully charged before starting the aircon.

Soft starters are typically for trying to get away with 2000w generators.
Tammy & Mike
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Grit_dog
Nomad III
Nomad III
OP, if it starts up on a standard 15a household circuit but not on the genny, it’s likely the genny. Off brand generators, specifically inverter generators are known for being hit or miss in their performance at the upper end of their ratings.
By comparison, I had no issue (9 out of 10 times) starting 2 differnet old 13.5k A/Cs with an old Honda 2000. A soft start would have made it a 10 out of 10 relationship! Lol.
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2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold

Grit_dog
Nomad III
Nomad III
Mike134 wrote:
Willie Jim wrote:
I'll try disconnecting battery. I see no circuit labeled battery charger in the breaker panel, guess it is powered through the main breaker.


If you do that than all the 12V loads will need to be powered from the generator via the 120/12V inverter.
If you could disconnect the inverter, then any 12V loads would be supplied by the battery.

Oh boy….
2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold

Grit_dog
Nomad III
Nomad III
KD4UPL wrote:
Your generator is likeky rated at sea level. Higher elevation reduces power output.

Considering the highest point in VT is a little over 4kft it’s highly unlikely that altitude is the culprit anywhere within a 2 day drive of his home, anywhere you’re gonna park a travel trailer.
2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold

deltabravo
Nomad
Nomad
Add a Micro Air Easy Start. They delay the start up of the compressor until the blower fan is up and running.

I love mine. My A/C never has an issue starting on my EU2200
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Willie_Jim
Explorer
Explorer
I'm on it!
Funny, I tell Mrs. I never see two same campers. We had a 2001 Outback 25 RSS we loved 20 years before this.

enblethen
Nomad
Nomad
A loose connection in the circuit could cause low voltage which increases amperage. Go through 120-volt distribution panel, disconnect each wire, one at a time. Clean the copper,and re-terminate. Do this to both hot wires and neutral.

Bud
USAF Retired
Pace Arrow


2003 Chev Ice Road Tracker

enblethen
Nomad
Nomad
NEC allows six breakers to disconnect panel circuits. More than six requires a main breaker.
It is not a charger, it is a converter1

Bud
USAF Retired
Pace Arrow


2003 Chev Ice Road Tracker

ktmrfs
Explorer
Explorer
Willie Jim wrote:
I'll try disconnecting battery. I see no circuit labeled battery charger in the breaker panel, guess it is powered through the main breaker.


NOPE, Main breaker only connects to the sub breakers. More than likely the charger is on one of the other breakers, likely one of the outlet breakers.
30A panel from what I've gathered only have 5 breakers per code. AC requires dedicated breaker, So does WH, Usually MW on it's own, that leaves 2 120V outlet breakers and the usually tie the charger to one of those.

Smart thing to do is to ditch code, add another dedicated breaker for the charger.
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enblethen
Nomad
Nomad
It is not an "Inverter" It is a "Converter"
Inverters change 12-volts DC to 120-volts AC
Converters change 120-volts AC to 12-volts DC.

Bud
USAF Retired
Pace Arrow


2003 Chev Ice Road Tracker

Mike134
Explorer
Explorer
Willie Jim wrote:
I'll try disconnecting battery. I see no circuit labeled battery charger in the breaker panel, guess it is powered through the main breaker.


If you do that than all the 12V loads will need to be powered from the generator via the 120/12V inverter.
If you could disconnect the inverter, then any 12V loads would be supplied by the battery.
2019 F150 4X4 1903 payload
2018 Adventurer 21RBS 7700 GVWR.

Willie_Jim
Explorer
Explorer
CA Traveler wrote:
Motors and especially heavier duty motors can draw substantial amps during startup. I just bought a 3,200 watt rated inverter gen with a 4,000 watt peak. I would not expect a problem with one A/C starting, 2 at the same time could be a problem. Will do some testing with the RV A/Cs because I want to know. I don't expect any issue with it's intended application of 2 household refers.


I'm intimately familiar with extra load starting motors, Air Conditioning tends to be worse than other loads. This generator claims to handle starting load twice that of full load amps. I hoped that meant a struggle to start, it'd take a second to get up to speed. It seems with more experimenting to sometimes manage to start the load. I'm leaning toward installing the soft start.

KD4UPL
Explorer
Explorer
Your generator is likeky rated at sea level. Higher elevation reduces power output.

CA_Traveler
Explorer III
Explorer III
Motors and especially heavier duty motors can draw substantial amps during startup. I just bought a 3,200 watt rated inverter gen with a 4,000 watt peak. I would not expect a problem with one A/C starting, 2 at the same time could be a problem. Will do some testing with the RV A/Cs because I want to know. I don't expect any issue with it's intended application of 2 household refers.
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Bob