MyReelSells

Generator size for a well pump

No power means no water on a well. Size for the pump's startup surge. We add the running watts and the startup surge, then show you the unit that fits.

On a well, losing power means no water for the toilets, the animals or the shower. A 1/2 HP submersible pump runs at 1,000 watts and starts at 3,000, and a 1 HP pump doubles that, so check the nameplate before you size. Most well pumps are 240V, which means a transfer switch or interlock at the panel, not an extension cord. The 12,500W dual fuel is the safe pick for a 1 HP well plus the house.

Step 1What has to stay on
OptionalHow big is the house?

Square footage is a rough guide. What sets the size is the biggest motor (pump, furnace, AC) and whether the fridge and freezer are on the list.

Showing essentials. Add coffee maker, microwave, washer, space heater, garage door, well pump, window AC →

Fits your numberThree ways to buy it
Storm season

Peak is the second week of September.

Statistically the busiest stretch of the Atlantic season lands around September 10. The units people want sell out in the three days before a storm, not after — that's the whole reason to size it now.

14days to peak
That load is standby-generator territory. Central AC or electric heat on top of everything else means a permanently installed unit and an electrician — or uncheck the biggest load and run it in shifts with a portable.
Sizing forA specific use
CampingTailgatingCPAP / medicalRV & van lifeHome office outageFishing & hunting campBackyard party & movie nightSump pump in a stormWell pumpChest freezer full of meatFood truck & farmers market
For thisWhat else you need
Generator interlock kit
The legal way to feed a 240V pump from the panel.
Amazon →
30A generator cord, 25 ft
Generator to the inlet box, outside.
Amazon →
Power inlet box, 30A
The outside plug the cord lands in.
Amazon →
Westinghouse 12,500W dual fuel
1 HP well plus the whole house.
Amazon →
Don't forgetEverything you need to get through the night

Safety, the short version: generator outside only, 20+ ft from windows, exhaust pointed away. Never plug into a wall outlet ("backfeeding") — it's illegal and can electrocute utility workers. Panel connections go through a transfer switch or interlock installed per code. Wattages above are typical; your appliance's nameplate is the truth — check it for anything critical like medical equipment or a well pump.

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Typical wattages compiled from manufacturer data; always verify against your own equipment. · myreelsells.com

Peak
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