Running both of my A/C units shut down my generator

[manderson2228]

Originally Posted by Freqz

The AC compressors are rated at 95 degrees: as you go up in temp you go up in current. By 115 it’s 4 amps per compressor [emoji33]. It’s a lot and something g I’m struggling with designing a system to keep me cool in West Texas on 30 amps.

I bet at 95 you fire up both just fine.

If it does, I wonder if the starting surge is getting you or the running amps? If it’s the starting sure a couple of $300 easy starts from micro air could be your ticket...

I'm not arguing with you on the amp increases at additional heat. I am just curious where you got that information. I've not heard that before and would like to read up on it a little bit.

[Freqz]

Originally Posted by manderson2228

I'm not arguing with you on the amp increases at additional heat. I am just curious where you got that information. I've not heard that before and would like to read up on it a little bit.

For instance:

https://www.airxcel.com/docs/default...e.pdf?sfvrsn=5

[twinboat]

If the engine was weak, bogging down, and unable to create enough power, it would slow down until the voltage dropped below 100 volts. At that point, the " Auto Transfer Switch " would open and the engine would recover, starting the cycle again in 30 seconds when it closes again.

If your engine is bogging down and dropping dead, its a fuel or ignition problem.

If the fuel system is in good shape, I would then suspect loss of ignition, possably from an overheat.

Here is a Harbor Freight ignition tester. Hook it up, run the generator until it shuts down, and see if it keeps sparking as it dies.

https://m.harborfreight.com/90-in-li...not%20provided

[tada]

Unfortunately I’m out of commission for a week. Yesterday afternoon I had an appointment with a retinal specialist for a large dark area in my vision. He found my retina had partially detached and I had emergency surgery. Now under his orders, I have to lay in bed for a week and can’t do any mechanical work.

By the time it heals, the temperature will have dropped and I’ll be able to do some more troubleshooting. Thanks to everyone for all the input, Tom.

[Freqz]

Ouch. Good luck and speedy healing!

[bldrbob]

Just realized when I run both ACs on the genny they are sharing the neutral which is true when plugged in but the difference is the genny legs are in sinc while shore power they are opposite canceling the loadWith the genny that means the neutral gets both sides of the load and is overloaded.Not sure I explained this right but the neutral got pretty hot.

[tada]

It’s 92° this morning and I had my wife start the generator and both ACs about an hour and a half ago. So far so good. It really may be heat related.

In my spare time I’ve been reading threads on the Onan generators. Apparently they had two fuel filters. One pre pump that attached directly to the pump, and a secondary filter that attached to the carb. When I tuned up the carb there was only one filter - the one attached to the carb which I changed. In one of the threads I read it said that that filter should be eliminated at replaced with an Onan adapter that has no filter and that the pre pump filter should be installed. Do you think that would help with fuel starvation issues under load?

[tada]

I let the generator and both ACs run for approximately five hours in 105° heat. I had to leave for a doctors appointment. The generator kept running the whole time. But I came back to find both ACs completely off with the Intellitec thermostat showing both ACs in a shed condition. I tried restarting them with the thermostat switch. Neither would come on. I finally powered everything down including the generator and contacted the shop who installed the ACs. They are hoping that a low voltage condition did not damage the circuit boards on the ACs. Not a good day for me.

Edit: I found the main 30A and AC 20A breaker in the coach had tripped. I reset them and have the 15k BTU unit running at present. So the AC units are still ok. But the Intellitec EMS is not shedding correctly. If it was, the breakers should not have tripped. Or the electrical part of the generator is acting up. Or it’s just too damn hot in the desert right now!

[twinboat]

Originally Posted by bldrbob

Just realized when I run both ACs on the genny they are sharing the neutral which is true when plugged in but the difference is the genny legs are in sinc while shore power they are opposite canceling the loadWith the genny that means the neutral gets both sides of the load and is overloaded.Not sure I explained this right but the neutral got pretty hot.

There should be 2 white, ( neutral ) wires coming from the generator.

[tada]

Ok, I fired up the rear AC and saw the EMS shedding correctly. But after about 10 minutes the rear compressor came on and killed the generator. Maybe adding two easy starts would solve this problem.

[leadman]

I had a TT that had a no name unit on it and it took about 22 amps to run it, and almost killed a 3500 watt generator to start it. IIRC it was a Chinese unit.
I have also seen u-tube videos where they starting draw on the Coleman unit on different coaches would draw about 85 amps on start up.
I have 35' Winnie with 2 small units on it and 30 amp service. Has a type of load controller that only lets one unit start at a time. I tested my units and they draw about 25 amps to start and each draws about 8 amps in the heat in Phoenix, about 6 amps here in Michigan.
Not sure if Coleman is still making their units or importing them but this is not the first I have heard of new units not wanting to run on the system that was powering the old ones.

[xrated]

Originally Posted by leadman

I had a TT that had a no name unit on it and it took about 22 amps to run it, and almost killed a 3500 watt generator to start it. IIRC it was a Chinese unit.
I have also seen u-tube videos where they starting draw on the Coleman unit on different coaches would draw about 85 amps on start up.
I have 35' Winnie with 2 small units on it and 30 amp service. Has a type of load controller that only lets one unit start at a time. I tested my units and they draw about 25 amps to start and each draws about 8 amps in the heat in Phoenix, about 6 amps here in Michigan.
Not sure if Coleman is still making their units or importing them but this is not the first I have heard of new units not wanting to run on the system that was powering the old ones.

What is the BTU rating on an air conditioner that only draws 8 amps?

[tada]

I’ve ordered two hard start capacitors from Amazon that will be here Tuesday. Looks like an easy install. I’ll report the results.

[gatorcq]

put them on LOW, then report back