So how many kW does a 2 ton ac use?

Who is the manufacturer?

Cooling phase? If so, and this is one you own can you check the tag (label) on the condensing unit outside for the amperage draw of the compressor + fan, it should be on that tag. For example, my 4-ton unit draws right at 20 amps (compressor + fan) - that information is on my condensing unit tag, but I’ve also checked it with an amp meter when the unit is operating and the values are very close.

Watts = amps x voltage. So 20 amps x 230 volts = 4,600 watts or 4.6 kW per hour while “running”. Add to that the amp draw of the blower motor in the air handler - not sure what that is without going into my attic and checking the motor but it’s not high, so maybe 5 kWh for my 4 ton unit for each hour of operation.

Heating - do you have electrical heating elements or natural gas? If natural gas, then just what the air handler blower motor uses - which again is not high. Electrical heating elements - add whatever watts or KW the elements are rated at for your unit.

That should get you pretty close. I’m not an engineer so engineers on the board will have to correct my math if I’m in error.

P.S., Now there is high in-rush amperage draw when the compressor starts which will up the numbers above somewhat - not sure how that is added in as that amperage draw, and hence kW consumption, is only for milliseconds.

It will probably run the AC unit but it may put you over the top if you have other things plugged in when the AC unit kicks on.

It’s a 15000kW starting and 12000kW running. If that helps. I’ll try to get that info to add to OP. Appreciate the answers!

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It’s a 15000kW starting and 12000kW running. If that helps. I’ll try to get that info to add to OP. Appreciate the answers!

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OK, the 15,000 starting watts @230 volts brings the starting amps to 65 amps. If the locked rotor amps (LRA) on your condenser plate is less than 65 amps then the generator should be large enough to start and run the 2 ton unit, particularly if a hard or soft start capacitor is added to the condensing unit (easy and inexpensive) with likely sufficient amperage to run the other items you mentioned in your OP.

I’ll be interested to see what others think and say that have first hand experience with this, particularly after you post the LRA and RLA of your 2-ton Carrier.

P.S. should note if you run the 12,000 kw generator on natural gas or propane it won’t generate as much kw as if running on gasoline - so that will need to be accounted for as well. .

A 12 KW with 15 KW surge should be plenty enough to run a 2 ton central unit, fridge/freezer, and should have enough left over to run a good bit if not all of your lighting/ tv loads. Especially if you have LEDs. A hard start on the condenser would not be a bad idea to help with the startup surge.

Your problem is going to be feeding that thing. It will be very thirsty if it’s gas, especially if it’s a 3600 rpm unit. It will probably have an 18 to 20 hp motor, and burn close to 2 gallons an hour at rated load.

probably around 1,700W or 1.7kW worst case. Due to inrush you'll want a slightly larger sized generator to handle the inrush during startup.

Any generator 3x larger should have no problems.

Thanks so much for the replies. If converted to be fed off of natural gas, I know it lowers the kw ability, but I assume it would still be enough to run the ac? Just trying to prepare for the next time this happens and I don’t have the space around my house for a whole home.

I’ve read up to 20% reduction in kW output converting a generator from gasoline to natural gas, Little to no reduction in kW output converting from gasoline to LP.

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