Parallel Yamaha generators can't run the AC now

[SATX_Camper]

New user here.

I have a TT with a 15k btu AC unit that function perfectly on shore power. Last year we bought a couple of Yamaha ef2000is generators and the parallel kit for boondocking, which we used a couple of times last year with no issue.

I'm getting ready for a trip next weekend and decided to pull out the generators and make sure everything was operational. The gennies cranked up with some fresh gas and ran just fine, powering lights, outlets, etc in the trailer. I turned off everything in the trailer and tried to turn on the AC and got nothing. Went to check on the generators and one of them had the overload light on.

I've tried several troubleshooting steps:
- with and w/o the Surgeguard
- checked all the fuses/breakers
- turned off breakers for everything but the main and AC

Anyway, I can't get the AC to run with the generators, but I know it is operational. Has anyone ever had this issue? Any ideas on how to resolve this?

Anthony

[2oldman]

MrWizard wrote:
WAnd were you trying to run both A/Cs at the same time

Both? All I see OP talking about is one.

[MrWizard]

What was the ambient temperature
And were you trying to run both A/Cs at the same time
That is not very likely
Try only one A/C, run on high fan for at least 5 minutes then switch to low cool, move to medium or high as needed

[MEXICOWANDERER]

Individually VERIFY each machine is capable of generating full nameplate power. This then will eliminate some possible answers, and perhaps spotlight a paralleling fault.

[icanon]

Did your try switching the Parellel cables to different inputs? Might not help but I believe in process of elimination.

[dclark1946]

Any chance you have extra ac loads such as water heater, fridge (in ac mode)or converter trying to charge discharged batteries?

You should get a clamp on Ammeter with peak capability to check steady state draw and startup current while running off shore power before starting troubleshooting your issue with generators. I have had issues with my Hondas load sharing equally when in a parallel configuration so there may possibly be an issue there.

If one generator went in overload mode I would expect the other to also since the A/C should still be trying to start.

Dick

[SATX_Camper]

2oldman wrote:
I assume the first statement means you ran the a/c on the yammies with no issue, so, why would there be an issue now?

With just ONE overload light on, I just had a crazy thought that maybe only that generator was successfully connected via the parallel cables. IE.. get out your ohmmeter and check those cables! I'm not clear on whether you've tried this with Eco throttle off (Honda's term for auto-load throttle).

And yes, your air won't come on right away after it's been running.

Yes, the AC ran on the generators last year with no problem, and yes, the economy mode was turned off. I wondered about the cables being bad myself, but will have to get one of my more electrical-minded friends to have a look at that.

[2oldman]

SATX_Camper wrote:
and the parallel kit for boondocking, which we used a couple of times last year with no issue.

Went to check on the generators and one of them had the overload light on.

I assume the first statement means you ran the a/c on the yammies with no issue, so, why would there be an issue now?

With just ONE overload light on, I just had a crazy thought that maybe only that generator was successfully connected via the parallel cables. IE.. get out your ohmmeter and check those cables! I'm not clear on whether you've tried this with Eco throttle off (Honda's term for auto-load throttle).

And yes, your air won't come on right away after it's been running.

[wld1985]

I've been reading up on doing this, it seems Harbour freight has the best price and wattage for doing this conversion. Then with there warranty ya can't beat it, 449.00 a piece and if ya drop it off the back of the truck and smash it into pieces ya get anew one

[SATX_Camper]

Thanks for the response Gordon.

The trailer is only a year and a half old, so I would guess that the start capacitor isn't old yet.

The AC was running on shore power for a little while before I attempted the generators so that could have been the initial issue. I attempted troubleshooting the generators for a couple of hours, taking a break to do an oil change and make sure the air filter was clean, cleaned the filter on the air return for the AC unit. So I would guess the AC had cooled significantly by the time I attempted to start it up again.

Three Yamaha's?! That's crazy talk! I'm guessing these people have a couple of AC units on their trailer and need the extra juice.

[GordonThree]

Start capacitor in the AC might be getting old? That capacitor limits the in-rush current going to the compressor motor, to keep it from tripping breakers / killing generators.

Did you have the AC running on shore power, turn it off, then try to start it again on the generators? Pressure in the compressor is higher than normal until the gas cools down.

Maybe it's time for a third Yamaha... folks on youtube doing crazy stuff with custom made parallel cables 🙂