My portable AC keeps tripping the breaker

Ladiesman

Super Active Member
Feb 6, 2018
840
To better understand, You have the pup plugged into the 30 amp outlet and the air conditioner plugged into the pup and when the compressor kicks on it pops the breaker on the generator? If you are only using the regular GFCI outlet on the generator to power everything and not the 30 amp which you need an adapter from 4 prong twist lock to 30 amp RV then its tripping due to pulling to much amperage. The regular outlet will be 20 amps. That AC just a guess probably pulls 12 amps. Now the pup added in converter running when the compressor kicks on you have over loaded the 20 amp circut.
 
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NLB

Active Member
Silver Supporting Member
Oct 10, 2021
502
West Palm Beach, Florida
Clearly, the generator is adequate size.
NOTE:The 30 Amp outlet on the Duramax provides 240 volts if I read the spec sheet correctly!!! Are you using an adapter?
Your PUP needs 110v only!
Your generator has a floating ground. You may need to use a plug that fixes that.
Hughes Autoformers Ground Neutral Plug https://a.co/d/1v224LR
What type plug on the air conditioner unit? 15 amp or 20 amp?
Can you plug the air conditioner into any outlet on your home power system?
Is the fridge off? What is the charge status of the PUP battery?
Try turning off all PUP breakers except the one for the A/C.
 
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Grandpa Don

Super Active Member
Sep 5, 2018
1,820
Southern California
To better understand, You have the pup plugged into the 30 amp outlet and the air conditioner plugged into the pup and when the compressor kicks on it pops the breaker on the generator? If you are only using the regular GFCI outlet on the generator to power everything and not the 30 amp which you need an adapter from 4 prong twist lock to 30 amp RV then its tripping due to pulling to much amperage. The regular outlet will be 20 amps. That AC just a guess probably pulls 12 amps. Now the pup added in converter running when the compressor kicks on you have over loaded the 20 amp circut.
Yep! That is what it sounds like to me too.
 

tcrawford07

Member
Jun 26, 2022
14
Northeast Texas
Clearly, the generator is adequate size.
NOTE:The 30 Amp outlet on the Duramax provides 240 volts if I read the spec sheet correctly!!! Are you using an adapter?
Your PUP needs 110v only!
Your generator has a floating ground. You may need to use a plug that fixes that.
Hughes Autoformers Ground Neutral Plug https://a.co/d/1v224LR
What type plug on the air conditioner unit? 15 amp or 20 amp?
Can you plug the air conditioner into any outlet on your home power system?
Is the fridge off? What is the charge status of the PUP battery?
Try turning off all PUP breakers except the one for the A/C.
The air conditioner is 110. Plugs into any wall outlet. No fridge in our pup. And no battery either. Pup didn't come with a battery. Is it supposed to have one? This is all new to me.
 

NLB

Active Member
Silver Supporting Member
Oct 10, 2021
502
West Palm Beach, Florida
No battery necessary for this issue.
Plug the air conditioner into a house outlet, that will assure it’s working properly.
Look at the link in my previous msg. Unless your generator is faulty, (try a heat gun, compressor, or other heavy load ), I suspect the issue is a floating neutral. The link I sent is the fix for that.
 

ChiefHart

Member
Apr 2, 2020
81
Staunton, Virginia
We have a Duromax 4850EH generator. And a TCL 8000BTU portable air conditioner for our 1985 Coleman Sequoia pop-up. But every time the compressor kicks in, the breaker on the generator trips. Both are brand new. What are we doing wrong
The AC compressor uses higher Amps when starting than your generator breaker. What is the Amperage of your generator breaker? It should be at least 20-A for an AC. Your AC will use lower Amps after the compressor has started, but the starting inrush of power is too much for your generator service.

I looked at the specifications of both of your pieces of equipment. Two possibilities 1. Breaker on the generator is defective, or 2. the Ac has a problem and draws more than 20-A on compressor startup even though it iis supposed to be able to use 120-V 15-A circuit. Maybe check ground on the generator, how is it grounded to earth? Might be some stray voltage that is tripping the breaker.
 
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tcrawford07

Member
Jun 26, 2022
14
Northeast Texas
No battery necessary for this issue.
Plug the air conditioner into a house outlet, that will assure it’s working properly.
Look at the link in my previous msg. Unless your generator is faulty, (try a heat gun, compressor, or other heavy load ), I suspect the issue is a floating neutral. The link I sent is the fix for that.
Thank you. Gosh, I pray this generator isn't faulty. I just bought it from Amazon.
 

Delberta Watson

OK Glampers
Jun 9, 2021
6
Oklahoma
We have a Duromax 4850EH generator. And a TCL 8000BTU portable air conditioner for our 1985 Coleman Sequoia pop-up. But every time the compressor kicks in, the breaker on the generator trips. Both are brand new. What are we doing wrong
We bought a Slow Start that my husband added onto the AC unit from the top. It helps so it doesn’t trip the breaker. It’s sold on Amazon but you’ll want to make sure it will work in your specific ac unit.

SoftstartRV SSRV3T by NetworkRV...
 

ChiefHart

Member
Apr 2, 2020
81
Staunton, Virginia
We have a Duromax 4850EH generator. And a TCL 8000BTU portable air conditioner for our 1985 Coleman Sequoia pop-up. But every time the compressor kicks in, the breaker on the generator trips. Both are brand new. What are we doing wrong
I found this on line:

8,000 BTU Portable AC Generator Size​


A portable AC with an 8,000 BTU cooling capacity requires a generator with at least a 4000-watt output. According to manufacturer requirements, 8,000BTU needs 800 watts when running and 1350 watts when starting.
 

bondebond

Super Active Member
Aug 14, 2008
2,330
Rather than guessing, I went and looked at the DuroMax 4850EH Generator and a TCL 8000BTU Portable A/C (I don't know if this is the exact model but it should be representative, being the same mfgr. and form-factor). The generator is a 120v/240v (depending on how you use the 30 amp outlet) , 120v 20 amp household outlet, dual-fuel generator with 4,850 starting and 3,850 running watts.

According to TCL's user manual, you need 120v AC at 15 Amps in order to run it. Unfortunately, the manual and nowhere on the manufacturer's website that I looked does it list any real electrical information, like starting wattage, etc. According to the seller on Amazon, it uses 700 watts when running (different than initial compressor start up). Depending on who you listen to, it can take more than double the running wattage to start up the compressor...so 1800 watts should be all you need. In theory.

Three major areas to troubleshoot here:
  1. Is generator good/strong enough?
  2. Is the wiring that you're using between the generator, through the PUP and to the AC sufficient in gauge and short enough length?
  3. Is there a problem with the AC?
Since you said that the AC works when plugged into Shore Power previously, we'll move past #3 for now.

And since you haven't given us how you are connecting the generator to the air conditioner (#2), that seems like a great place to start by getting rid of it from the situation for now. It could simply be too small of a wire gauge over too long of a length.

Have you tried plugging the air conditioner directly into the 120v 20 amp plug on the generator? Bypass all PUP-related wiring issues by doing the simplest thing to try - and it doesn't cost any money to try it. Does the AC work properly when plugged in directly to the generator?

If that fails, then you may indeed have a problem with the generator, or possibly the air conditioner but more likely the generator. It is good that you have tried the AC on Shore Power in the PUP before so we know the AC works. However, I would still try plugging it directly into the generator and see how the generator performs.

If it DOES work fine, then we move on to area #2 above.

Let us know how plugging it directly into the generator turns out. No extension cords, just straight in.

As a frame of reference, I use a pair of 2,000 watt Inverter-based generators with a combined starting wattage of 3,000 to run a 13,500 BTU roof mounted air conditioner. Your generator should be sufficient as far as wattage goes, but it might not be clean enough for the sensitive electronics inside the AC. I have a similar 8k BTU portable AC that I bought specifically to run off of one of my 2,000 start/1,600 running watt Inverter generators and it does not have a problem at all. I say all of that to say that just because the numbers look good, doesn't mean you have a compatible system configuration.
 
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ChiefHart

Member
Apr 2, 2020
81
Staunton, Virginia
Rather than guessing, I went and looked at the DuroMax 4850EH Generator and a TCL 8000BTU Portable A/C (I don't know if this is the exact model but it should be representative, being the same mfgr. and form-factor). The generator is a 120v/240v (depending on how you use the 30 amp outlet) , 120v 20 amp household outlet, dual-fuel generator with 4,850 starting and 3,850 running watts.

According to TCL's user manual, you need 120v AC at 15 Amps in order to run it. Unfortunately, the manual and nowhere on the manufacturer's website that I looked does it list any real electrical information, like starting wattage, etc. According to the seller on Amazon, it uses 700 watts when running (different than initial compressor start up). Depending on who you listen to, it can take more than double the running wattage to start up the compressor...so 1800 watts should be all you need. In theory.

Three major areas to troubleshoot here:
  1. Is generator good/strong enough?
  2. Is the wiring that you're using between the generator, through the PUP and to the AC sufficient in gauge and short enough length?
  3. Is there a problem with the AC?
Since you said that the AC works when plugged into Shore Power previously, we'll move past #3 for now.

And since you haven't given us how you are connecting the generator to the air conditioner (#2), that seems like a great place to start by getting rid of it from the situation for now. It could simply be too small of a wire gauge over too long of a length.

Have you tried plugging the air conditioner directly into the 120v 20 amp plug on the generator? Bypass all PUP-related wiring issues by doing the simplest thing to try - and it doesn't cost any money to try it. Does the AC work properly when plugged in directly to the generator?

If that fails, then you may indeed have a problem with the generator, or possibly the air conditioner but more likely the generator. It is good that you have tried the AC on Shore Power in the PUP before so we know the AC works. However, I would still try plugging it directly into the generator and see how the generator performs.

If it DOES work fine, then we move on to area #2 above.

Let us know how plugging it directly into the generator turns out. No extension cords, just straight in.

As a frame of reference, I use a pair of 2,000 watt Inverter-based generators with a combined starting wattage of 3,000 to run a 13,500 BTU roof mounted air conditioner. Your generator should be sufficient as far as wattage goes, but it might not be clean enough for the sensitive electronics inside the AC. I have a similar 8k BTU portable AC that I bought specifically to run off of one of my 2,000 start/1,600 running watt Inverter generators and it does not have a problem at all. I say all of that to say that just because the numbers look good, doesn't mean you have a compatible system configuration.
I like your reply, I also would suspect that the output curve of the generator to be "dirty", square wave versus pure sine wave. Plugging directly into the generator should help identify the problem. That fits your outline of diagnostics.
 

tcrawford07

Member
Jun 26, 2022
14
Northeast Texas
And we have the pup plugged in to the big plug with RV adapter. I just don't understand it. That is a brand new generator and at 4850 starting watts and 3850 running watts, it should carry that AC. And I mean just the AC.
 

NLB

Active Member
Silver Supporting Member
Oct 10, 2021
502
West Palm Beach, Florida
The switch on the generator control panel is a possibility.
Try moving it to the right.
120v. Not having the operation manual to read, but I think the 120/240 isn’t what you want.
After that, I think the floating neutral plug for $14 is your best bet.
 




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