Generator overloads with A/C

[mesoman7]

I know this topic has been beaten to death, but I am at a loss. My Champion 3100 immediately overloads when the a/c is turned on. The a/c unit is 13.5K BTU, so the gen should handle it. My older gen has a higher capacity. It would start up the compressor. After a minute or two, it would start to motorboat then trip the 30A breaker. I can run the a/c connected to the house on a 20A circuit with no problem. OK, to mitigate the normal questions:

Refer - off
Microwave - off
Water pump - off
Water heater (elec) - off
I even shut off the converter

What am I missing here?

- Jeff

[marcsbigfoot20b]

pianotuna wrote:
marcsbigfoot20b27,

Thanks for taking the time to test and post the results.

Lol, worst test conditions and worst AC. I just checked the manual at 59 locked rotor amps.

Too bad there are no performance parts for the EU2000i like carb, head, cam etc.

[pianotuna]

marcsbigfoot20b27,

Thanks for taking the time to test and post the results.

[marcsbigfoot20b]

Update: Not going to happen.
I give the poor little Honda 2000 credit, second try it fired up the compressor for 5 seconds but didn't have enough watts at these temps.

Tested at 120.2 degrees in the shade, TT in the sun all day with AC set at 80, removed shore power and ran E2000i on high. I even put in low fan for an extra few watt savings. Compressor cycled back on but couldn't handle it. At 100 degrees it could, but the extra 20 degrees made a big difference, both higher head pressure and lower hp. Just needed about 200-300 more watts at these temps.....or a hybrid inverter charger.
The gas was about a year old, but I doubt it made a difference in a sealed metal can.

On shore power the interior was holding 82 inside with a 58 output of the AC.
Of course I didn't start this till it was 96 inside and 105 outside, lol.

[marcsbigfoot20b]

I am going to say no on the Eco switch for this test.
At 1400 ASL and 120 degrees in Phoenix there will be about 8% power loss...... So maybe 12.1 amps which is maxed out RUNNING......starting, even worse.

Just calculated....more like 83% of rated power !!
According to the DA altitude calculator (density altitude) it will be equal to 5700 ft. Which would be 83% even worse than I thought. 1600/2000 is now a 1328/1660 generator.

It might not work. That's only 11.0 amps running (@95 degrees) and it will be worse.

[TurnThePage]

I too am hugely curious how it works out!

[SoundGuy]

Bobbo wrote:
Rather than a hard start capacitor, this video shows what I will buy if DW ever decides I need a generator.

EasyStart module

marcsbigfoot20b27 wrote:
I just installed one of those. It works.
I'm going to test it out today at about 3-4 PM with my EU2000i when the ambient temp should hit 120 degrees today.......the ultimate test.

No kidding! 😉

Curious minds would also like to know if your EU2000i has to be running with ECO off or whether even under these extreme conditions the Easy Start allows your genset to manage the load with ECO turned on. :@

[marcsbigfoot20b]

Bobbo wrote:
Rather than a hard start capacitor, this video shows what I will buy if DW ever decides I need a generator.

EasyStart module

I just installed one of those. It works.
I'm going to test it out today at about 3-4 PM with my EU2000i when the ambient temp should hit 120 degrees today.......the ultimate test.

[MrWizard]

If it has a bad start capacitor
A new start capacitor is the simplest solution
The microwave air easy start
Can be added at a later date, if deemed necessary

[Bobbo]

Rather than a hard start capacitor, this video shows what I will buy if DW ever decides I need a generator.

EasyStart module

[mesoman7]

Took a look inside my a/c unit. Looks like a snap to install a hard start cap, so that's what I'll do.

Now for some humor. I contacted a local RV dealership and laid out the problem. Their "solution" was to get a bigger generator. When I asked about a hard start cap, they had no idea what I was talking about. Called dealer #2. "Need a bigger generator". Was rather unmoved about the hard start cap.

So much for the "professionals".

Now I know where to go for tech advice...right here. Thanks for the help. I'll let you know how it turns out.

[kzspree320]

Here's a video that shows how to test and replace. Sounds like your issue. Hope it helps.

CLICK HERE

[MrWizard]

unplug some wires and screws,
put the new one on

take a couple of pictures first

you want to get the wires back on the right posts
the just push on 1/4 spade posts
usually 4 or 5 wires

[mesoman7]

UPDATE. I tried putting other heavy loads on the gen (water heater, microwave) with no issues. Then I switched off every breaker except for the a/c. Switched on the a/c (after running the fan for several minutes), and immediately overloaded and cut the power.

Looks like it is what several of you suspected - the capacitor. I'll talk to one of the local RV service depts and see what they say.

How difficult is it to install one DIY? My unit is a Coleman-Mach 4800 series.

[mesoman7]

MrWizard wrote:
The start capacitor is suspect
But also when did you start it
Did you wait until it was 90 in the RV
Did you run the a/c fan for 5 to 10 minutes to remove system heat and reduce head pressure before turning it to cold mode

Temp was only in the 70s, and inside maybe 80. I did turn on the fan first, but only for about a minute.

[mesoman7]

kzspree320 wrote:
mesoman7 - you said "My Champion 3100 immediately overloads when the a/c is turned on." So what exactly does it do? You described what happened when your old generator started it, but not this one. Does it throw the breaker? Bog down and die? Or does the compressor and fan just not come on?

If I turn the fan on, the gen bogs momentarily then it is fine. When the a/c tries to start, the gen immediately overloads and cuts the power.