Running AC On Portable Generator

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I have a portable generator that is rated at 7,500 watts run and about 14,000 start. I have a 10 seer (sp?) central AC. Is it possible to run the AC from the generator if nothing elese is attached to the generator?
Thanks.
IC
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10 seer is the efficiency of the machine (low) you need to give the full load amperage of the condenser and the blower as well as the voltage of the blower

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The condenser is 240V, but the blower fan is 120. The generator will work at 240 (though I'm not sure it is wired in through the panel at 240).
-- IC

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You still need full load amperage of both units. It would have been better if the blower was 240 as well. Your generator puts out aprox 31 amps @240 volts continuous. The blower at 120 volt probably needs around 10 to 12 amps. Look on the nameplate of the condenser for the FLA

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Really Highly Doubt it that you will be able to run the AC off of your portable Generator - Seeing that it is going to be a pain in the ass to have the 240 and the 120v coming off your generator at the same time, and not to mention unless you have a really big portable generator its not going to supply the current you need to get that A/C up and running. That Start-Up Current Spike is going to be way over what your generator probably can supply thus it will trip everytime.
Joe

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My parents ran the A/C from their portable many times. Living in rural NC they got their power knocked out a lot by storms. The 240/120 wasnt an issue. They just back fed to the house load center and ran things normally. They just couldnt run the A/C and water heater at the same time.
Joe Grassi wrote:

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Practically all generators with a 7.5 kw output generate 120/240 volts. The OP's issue is his combined starting and running current, which is still unknown. If his unit is small enough, it would work fine

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Backfeeding through the main panel without a transfer switch is dangerous as hell and in most places illegal

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You are right. They always disconnect from the main power before running off the gen.
Noon-Air wrote:

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That ain't true.
Backfeeding through the main panel with a suicide cord is illegal in some areas (should be in all areas), and backfeeding without disconnecting from the utility drop is also generally illegal.
But a backfeed with a proper cord or wiring, plus a break- before-make connection should be perfectly legit. And perfectly safe. Farmers have been using huge double-pole/double-throw switches for eons when they backfeed in an emergency.
Gideon
============ Noon-Air wrote Backfeeding through the main panel without a transfer switch is dangerous as hell and in most places illegal.

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Gideon wrote:

Those huge double-pole/double-throw switches you mentioned are transfer switches. By definition a "back feed" involves sending current through a circuit from a point on the circuit that is not it's normal source of supply. -- Tom Horne
Well we aren't no thin blue heroes and yet we aren't no blackguards to. We're just working men and woman most remarkable like you.
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Damn, I am the victim of my own failure to distinguish vernacular vs NEC definitions. Thanks for the correction.
Now, if you can help me find a big-assed DPDT switch that isn't overpriced by a factor of 10. (Yes, I know - low production items always sell at a premium.)
Gideon
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dangerous as

Wouldn't a double pole cutoff be insufficient? I assumed the neutral must also be disconnected from the power company's outside line. Isn't it going to be carrying current when the generator is running?
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IC_Clearly wrote:

Probably is OK. You can try it. If it doesn't trip the gen breaker then you're ok.
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IC_Clearly writes:

Even the smallest split system will require far more starting current than that generator could provide.
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Richard J Kinch wrote:

I would think that something under 24000 BTU (2.4 KW) would probably start OK, even if it didn't have a hard start kit on it.
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24000 Btu is 7 kilowatt-HOURS of energy. We might make 24K Btu/h of cooling power with 2.4 kW of electrical power...
Nick
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snipped-for-privacy@ece.villanova.edu wrote:

Only at 10 SEER or better.
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My 2-ton 12 SEER heat pump outdoor unit draws about 6 to 8 amps at 240 volts when running. Start amps are about 20 to 25 amps. The indoor unit draws about 2 amps at 240 volts. I use a window unit during power outages, 120 volt, 1/2 ton. Then I can also run two refrigerators, a microwave, the TV if the cable still works and some lights. I also run a cord to each of two neighbors so they can run their refrigerators too. If I ran my heat pump, it would reduce what Extra stuff I could run.
What size is your AC? That would determine the answer. If it is much over 3 tons, probably not.It depends on the surge rating of the generator and if you have a hard start kit on your ac. My heat pump has one, but I still prefer the window unit. Why strain an expensive generator?
Stretch
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Stretch,
I mentioned in another post I am leaning toward the window unit plan now (thanks to all the good info here). I am considering three or four 6 btu units spread throughout the house. My generator is 7500 KW run and 13.5 KW start, so I'm thinking I should have plenty to do about what you described you do. Some lights, window AC, refridge, micorwave, TV and computers.
Thanks.
-- IC

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