techkiller80
I am building a new house and ended up buying a Generac 70432 22Kw standby.  The house will be about 2900 sq ft when finished.  After lots of research i decided on this unit.  We will be hooking it up to natural gas.  Did i make a good choice?  I'd love some feedback from others who own this unit or have experience with it.

Thanks 
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Peddler
That is our most popular unit and we regularly switch the whole house with it.  Excellent choice. 
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nrp3
I have good luck with these as well, though I’d like to know what it’s connected to for loads to really know it’s appropriate for your home. 
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Geoff Z
That model typically runs close to 50% of all generators we sell. As nrp3 says if sized properly for your application you will be very pleased.
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george6488
You did do an estimated load calculation? This unit should work perfect on most houses. Enjoy
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techkiller80
nrp3 wrote:
I have good luck with these as well, though I’d like to know what it’s connected to for loads to really know it’s appropriate for your home. 


New house will have basic kitchen appliances (Gas) 2.5 baths no jet tubs or anything, roughly 2950sq ft house but basement is unfinished for now.  No whirlpool or anything though we may add one in the future
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JayH


New house will have basic kitchen appliances (Gas) 2.5 baths no jet tubs or anything, roughly 2950sq ft house but basement is unfinished for now.  No whirlpool or anything though we may add one in the future


Air conditioning is a factor you need take into consideration. If your kitchen appliances, clothes dryer, and water heater are gas and you don't have A/C it may be more than you'll need, but it's far better to be oversize than undersize. If the entire 2950 square feet is air conditioned it might not be big enough, or you might need to do some soft start/load shed tricks to handle the A/C.
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78buckshot
At 3000 sq. ft. I'm guessing you have more than one furnace and a/c, 5 -7 tons?
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techkiller80
78buckshot wrote:
At 3000 sq. ft. I'm guessing you have more than one furnace and a/c, 5 -7 tons?


Very good question....the house is around 2050 sq ft, basement 900 sq ft.  It will be a daylight basement and unfinished.  As far as i know it's just 1 furnace and 1 AC but i'll def be talking to my HVAC guy.
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Wireform


Very good question....the house is around 2050 sq ft, basement 900 sq ft.  It will be a daylight basement and unfinished.  As far as i know it's just 1 furnace and 1 AC but i'll def be talking to my HVAC guy.
AC @ 3.5 ton should be adequate for the square footage with it being new consruction.
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78buckshot
OK, that makes a difference. 2000 - 2100 sq. ft. finished living space, one furnace/ac, 80,000 BTU heat and 3 tons cooling - the generator should be fine.
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Wireform
22kw is definitely overkill but as they say more is better. Assuming the 80,000 btu is NG all you have is light amp draw on the electrical for the pump/circulators.
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Goofy4TheWorld
Wouldn't the heat BTUs and cooling tons be determined by what part of the country this house is in? I would think a 2000 square foot house in Maine would need a whole lot less cooling than one in Florida, but I'm just speculating.

If I was building a new house there is no way I would run my entire electric service through the transfer switch.  I would have a small 200 amp disconnect as my service panel, a disconnect that has a 200 amp main, plus 8 to 16 spaces, and feed through lugs at the bottom.  Then you feed the transfer switch with the feed through lugs, you can even use a non-service-rated transfer switch.

You would then have the ability to add anything in future which you would NOT want on the generator (such as basement HVAC, pool pump, garage air compressor, electric car charging, pot growing lamps, etc..) without having to use a shed relay or a shedding contactor.  

Doing this during new construction will cost only a few hundred bucks, doing it later will be a huge pain and much more expensive.
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Goofy4TheWorld
Actually, me personally, for a house that size I would have a 400 amp service, one 200 amp box on the generator,  the other 200 amp box not on the generator.  Still only need a 200 amp transfer switch. But where I live the electric company doesn't require you to justify a 400 amp service,  but it's my understanding some utilities don't allow you to go way overkill on service size. 
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Wireform
Most utilities are not giving you a 400 amp service on a 2400 square foot home. 200 amp has plenty of room and a 22kw generator with load shed is more then you need. When there's NG the furnace and dryer are not electric so not much else for a massive load. I have a 2400 sq/ft home ,200 amp service with a 12kw generator. The only thing not int the transfer swith is my AC which I'm told can be with a load shed and a soft start kit.
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Goofy4TheWorld
But it could be a 3000 square feet house if the basement is finished.  A 3000 foot house with all electric appliances and HVAC would be beyond a 22kW generator, and well within reason for a 400 amp service. 

But I freely admit my utility companies are very amenable (gas and electric) where many others are not!  
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78buckshot
Yes Goofy, the location does have bearing on the size of the heating and cooling equipment, I was just generalizing based on my location which is southeast lower Michigan. Our load calc's for heating are based on a zero degree day and for cooling on a 90 - 95 degree day. Basement is rarely considered when sizing the cooling due to the cold dense air wanting to settle in the low area. Heating a basement is best done with in - floor radiant or perimeter baseboard but thousands of homes are usable with forced air in the basement. My comment hinged on the original post of a 3000 sq. ft. home shrinking to 2000 sq. ft. and the approximate equipment that would go along with those. I think we have concluded that a 22kw will be just dandy for the new homeowner and everyone has helped him feel comfortable with that choice.
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BrianMartin
Most new homes I find can easily be powered with an 11 KW, and a SMM on the AC. Unless all of the appliances are electric (unusual in this area) or the customer wants a hot tub or some other large load backed up, an 11 KW is lots of power. Once you start adding multiple SMM's, it usually makes more sense to upgrade to a larger KW. My 2 year old 2500sq/f +900 sq/f finished basement home with all NG appliances and a 3 ton AC is backed up easily on a 14KW. 
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techkiller80
BrianMartin wrote:
Most new homes I find can easily be powered with an 11 KW, and a SMM on the AC. Unless all of the appliances are electric (unusual in this area) or the customer wants a hot tub or some other large load backed up, an 11 KW is lots of power. Once you start adding multiple SMM's, it usually makes more sense to upgrade to a larger KW. My 2 year old 2500sq/f +900 sq/f finished basement home with all NG appliances and a 3 ton AC is backed up easily on a 14KW. 
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techkiller80
Thanks for the feedback guys and yeah from what i understand going with the 22kw is an overkill well 19kw on natural gas as i understand it and we will obviously be load concious if the generator is running.  
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Cobranut

Wouldn't the heat BTUs and cooling tons be determined by what part of the country this house is in? I would think a 2000 square foot house in Maine would need a whole lot less cooling than one in Florida, but I'm just speculating.

If I was building a new house there is no way I would run my entire electric service through the transfer switch.  I would have a small 200 amp disconnect as my service panel, a disconnect that has a 200 amp main, plus 8 to 16 spaces, and feed through lugs at the bottom.  Then you feed the transfer switch with the feed through lugs, you can even use a non-service-rated transfer switch.

You would then have the ability to add anything in future which you would NOT want on the generator (such as basement HVAC, pool pump, garage air compressor, electric car charging, pot growing lamps, etc..) without having to use a shed relay or a shedding contactor.  

Doing this during new construction will cost only a few hundred bucks, doing it later will be a huge pain and much more expensive.


I don't think that 22kW is overkill at all for the OP's application.

Goofy,  There's no way I wouldn't want everything on my system backed up by the genset.
I had a 400a service installed when I built the house.  All I had to do was tell the utility what service I wanted, I don't recall any evaluation to determine if I "needed" 400a.

With a 50a branch to the attached garage, 50a to the detached garage, 100a to the shop, 50a to the coach storage building, and 30a to the tractor shed.  I also have a 27kw tankless water heater.  Along with the heat pump in the house, and furnace/AC on the shop and garage, the load adds up in a hurry.
It's nice that we can still go about life as usual during an extended outage, though I once had to remind my wife, after our 30kW diesel shut down on overload, that she couldn't run EVERYTHING in the house at once. 🙄

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