Ok… I’m a bit stymied here, and I’m turning to the collective hive mind around here figuring someone knows how this works.
So I got a generator recently for free, and have converted it to run on the natural gas line from my grill. Works fantastically well, for what that’s worth. The only catch is that it downrates a little bit (~20%) from the wattage ratings running from gasoline. On gasoline, the generator makes 3300 watts of electricity for normal loads, and can support surges as high as 4000 watts. On natural gas, that’s 2640 watts and 3200 watts respectively.
I got to wondering if that’s enough to run two refrigerators. From what I’ve read, a fridge has a startup current that’s as much as 4x the running current. Problem is, the only information I can find on my fridges is the voltage and amperage- both are 8.5 amps @ 115 volts, for a grand total of 977.5 watts. And the manual says I need to connect it to its own 15 amp circuit, which implies a maximum wattage of 1800 watts (15 x 120).
My question is what is that 977.5 watts? Is that the running current- the compressor motor and fans draw nearly 1000 watts just running, and up to 1800 watts to start up? Or is that the surge current, and the running wattage is more like 250-300 watts?
Also, is that high startup current every time the refrigerator cycles, or just when it starts up for the first time?
Typical fridge running power is 300-500W.
But, defrost power might be even more than that.
Startup power can be over 1000W for a second or so. Sticking a data logger on the fridge would give you a better idea of your actual power consumption, but I’d bet that your generator would be able to run both at the same time, but not much else, unless you could guarantee that they both won’t start up at the same time (which is probably impossible to do).
When the power goes out I run the house on a 3600 W generator. The only high-current loads I keep powered are our two, full-size refrigerators. All other high-current loads (air conditioning, range, clothes dryer, and two microwave ovens) are kept off.
The generator has no problem powering the two refrigerators.
Thanks! It seemed like 1800 watts to start up was high, but I wasn’t sure.
My plan in case of an outage is to run the fridges, and in the summer, maybe a fan or two. In the winter, I might just alternate running each fridge for a few hours, and run a space heater if it’s cold enough to need that. Last time our power went out, it wasn’t that cold. Enough to be uncomfortable without heat, bot not life threatening or anything like this last February.
Also check if your generator is inverter based and if your refrigerator requires an inverter generator. Newer refrigerators have sensitive electronics and need inverter generators.
Same goes for charging / using devices that have sensitive electronics in them : laptops, phones, chargers etc - all do better with inverter generators.
Also Volts x Amps does not equal Wattage for AC motors. VoltsxAmps gives you VA that needs to be multiplied with power factor to give you wattage. The power factor is usually greater than 0.8 for refrigerators.