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Need help with home generator

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Hello.
I understand this is a forum for professionals, but I have been going in circles trying to find an appropriate home emergency AC generator to power an air conditioner for my elderly parents.
They live in So Cal. and extended blackouts are expected this summer.
The problem: I purchased a 3000 watt Coleman generator (3600 surge) to run a 10 amp, 120 volt air conditioner. When I tried to run the air conditioner, the compressor would not start.

(The name plate on the AC says it requires a 15 amp breaker)

When I called Coleman they said I need at least a 5000 watt, and probably a 7000 watt just to start it. Also, they said I cannot draw the full/max rated currant from one receptacle on the generator.(part of the problem ?)

I would like them to be able to run the air conditioner, but I don't want to buy a 7000 watt industrial generator just to run a 1250 watt AC.
Any suggestions would be greatly appreciated as I have not been able to get any help from electricians, generator sales or manufacturers.
Thank you.
 
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Sounds like Coleman gave you good advice.
Your generator is probably 120/240 V, which means it can supply 3000 W to a 240 V load, or 1500 W to each of two 120 V loads. The 10 A figure probably refers to full load current. Motors draw significantly more during starting (NEC says a 115V 9.8 A full load single phase motor draws 58.8 A while starting) This current doesn't last long enough to trip the 15A breaker, but does cause problems for a generator.

Another option might be to rewire and/or replace your motor for 240 V operation.
 
Suggestion: It is good idea to shop around and mention your load. There are other generator manufacturers, e.g. Basler/Kato, etc. If a generator is designed for the motor load, it may have a flywheel, the protective device (a time delay fuse 1.75 x Full Load Current) is also designed for the motor load and one does not have to have an excessive surplus of Watts. A solution might be either to trade it for the larger one, or add a flywheel, or try a soft start of the compressor motor over a soft motor starter.
 
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