What size genset for frig?

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Have a 2011 Maytag kitchen refrigerator, tag says 7.1 amps. Does not say if this is running or starting surge amps. Seems like a ton of amps for running, at around 800+ watts.

For those of you with frig/gen experience, what size generator output am I looking for with this frig? I'd like to stay around 2,000 watts surge rating for fuel efficiency reasons, but I am fearful that is nowhere near enough starting surge power. Opinions welcomed...
 
Amps X Volts=Watts.

Always figure heavy. 12 amps(a guess) starting would need
1400 watts, so 2000 should work if that's all your feeding.


My 2¢
 
Google How many watts does it take to run a refrigerator on a generator?
Many devises need more power to start up (Maximum Output Watts) and then require less power (Rated Watts) to run continually. For example, a refrigerator requires 2200 starting wattage with a 700 running wattage, so you would need a generator with at least 2200 watt maximum output.

Honda says less https://powerequipment.honda.com/generators/generator-wattage-estimation-guide
 
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Many of the starting load requirements are overstated and drive to buying oversized and thirstier generators.
 
I have also done it with my HF 800 watt two-smoke.

What I did to get it going was I ran a power strip at the end of the extension cord with a hair dryer on it on low (800 watts) to load the generator then I killed the hairdryer while simultaneously plugging in the fridge. In the time since, I think I broke said generator in as it makes more power and I don't have to do the hair-dryer thing.

But my kill-a-watt meter says my fridge takes 280 watts running. It's a whirlpool with 6.5 Amps on its data plate.

Beware the defrost cycle, about 2x a day, runs on a timer and uses a bit more power.

That all said I'd get a small 4-stroke generator of the 1500 watt sizing for efficiency. 2-strokes blow 10+ percent of the incoming gas straight through the exhaust.

Take note that a conventional 3600 RPM non-inverter generator has an engine flywheel spinning along, so when it's suddenly loaded, the flywheel carries it through. Generally enough for the compressor's locked rotor inrush current.
 
Originally Posted By: eljefino


Take note that a conventional 3600 RPM non-inverter generator has an engine flywheel spinning along, so when it's suddenly loaded, the flywheel carries it through. Generally enough for the compressor's locked rotor inrush current.


Great observation. Something like a 5500 BTU AC will usually trip the breaker on a 1000 watt inverter unit, but start OK on that little HF unit.
 
With a Honda 2000 inverter gen, I was running a std refrigerator ~ 600 Watts, a 46 inch TV ~ 300 watts, 2 60 watt lights and a computer without any issues for 3 days continuous except for gas fill ups. Ed
 
So a fridge is basically an A/C compressor. Load side pressure is low at start-up unless it is running nearly continuously (?). That motor starting load is based on starting current to come up to speed and then running current based on compressor load. The starting current is mostly fixed. The compression load varies depending on how long between cycles. And that depends on delta T between ambient and internal temps and insulation value ...

You need to factor worst case. 110* outside and the house is hot and the wind is blowing and tree goes down. Now you have to generate enough t start a frequently cycling refer. More load.

Never skimp on gen set. You will just hurt the gen set and maybe your appliances. Better to get a bigger gen set and a more efficient motor, than a smaller gen set ...

Fuel is cheap. New refer, not so much ...
 
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The Honda EU2000 will do it with zero effort, as I've done it for weeks.

The suggestion above is a good one a small generator with 4 stroke engine will also do it without any issues. Champion makes an 80cc, 4 stroke, 1200w/1500w unit that would easily and efficiently run the fridge, with power left over for lights. They used to sell for $99 but are now about $180-200, and are known to last thousands of hours.
 
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Kuhlshrank is refrigerator
smile.gif
 
Maybe you can extrapolate something from my experience with a Champion 3500 watt running / 4000 watt peak generator. I've managed to run three refrigerators and one 15 cubic foot freezer simultaneously. One refrigerator and freezer are on the same circuit, so there is a pretty good chance that they start at the same time when that circuit gets energized. That's the first circuit I energize, and the generator does slow down momentarily. It doesn't bog down.

I've also got the gas range with electric ignition wired to the generator via a transfer switch. The electric ignitor for the oven has a more noticeable impact on the generator than the refrigerator and freezer starting, but then the generator is more heavily loaded at that point.

One thing yet to be mentioned in this thread is that a refrigerator is an inductive load. There will be a momentary drop in voltage when it comes on, which will reduce the current it draws. I've seen guidelines for commercial applications suggesting that you can get away with 70% of the nameplate starting amps because of this. In your case, that means you should be fine with 5 amps or perhaps as little as 600 watts. That latter figure does seem consistent with some of the other advice posted here.
 
Originally Posted By: BrocLuno
So a fridge is basically an A/C compressor. Load side pressure is low at start-up unless it is running nearly continuously (?). That motor starting load is based on starting current to come up to speed and then running current based on compressor load. The starting current is mostly fixed. The compression load varies depending on how long between cycles. And that depends on delta T between ambient and internal temps and insulation value ...

You need to factor worst case. 110* outside and the house is hot and the wind is blowing and tree goes down. Now you have to generate enough t start a frequently cycling refer. More load.

Never skimp on gen set. You will just hurt the gen set and maybe your appliances. Better to get a bigger gen set and a more efficient motor, than a smaller gen set ...

Fuel is cheap. New refer, not so much ...


That depends upon how long you are running, and if said conditions are practical/relevant.
 
I was doing the same thing but it sounded like that Champion was having labor pains = so just upgraded to 6000 watt and doing all three was easy during Harvey (luckily just 5 hours and power restored)
My (2) Champions are now back up gens or I’ll run a window unit AC and fans/lights with them on opposite end of house
 
I have a Champion 3500/4000 surge generator. We had a power outage and it ran 2 refrigerators, a mid size chest freezer, and a handful of lights and the tv.
My Champion 1700/2000w inverter will run a fridge with ease.
 
figure 200w running 800w startup.
modern fridges are pigs.
make sure you skip the defrost and door heaters.
in an emergency you can forgo those for a while.
btw i ran a 1935 ge monitor top on a 400w inverter at a remote garage.
it uses around 75w.
the inverter was a cheap cobra unit that i expected to blow up.
it ran all weekend even with the solar bank in eq around 16v.
a small by todays standards but very durable and efficient fridge.
and i got it free.
folks had no idea what they gave away.
 
Originally Posted By: Donald
I would buy or borrow a clamp on ammeter with peak hold. Before spending money on a generator.

+1
I have a small refrigerator that only draws 110 watts when running but my 1000 watt (2000 watt surge, supposedly) sine wave inverter would not start it and my 1600 watt generator struggled to start it. After checking it with a peak hold ammeater I discovered that it was drawing a peak of 16 amps at startup! It is my understanding that this is fairly typical of the newer more "energy efficient" refrigerators.
 
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