MyReelSells

Generator size for a sump pump

The basement floods when the power dies. This keeps the sump running. We add the running watts and the startup surge, then show you the unit that fits.

The storm that knocks the power out is the same storm that fills the sump pit, so this is the one outage load that cannot wait. A 1/2 HP pump runs at about 1,000 watts but starts at 2,000 or more, and that surge is what sizes the generator. A 3,500W inverter covers the pump alone; the 6,500W dual fuel covers the pump, the fridge and the furnace fan. Run it outside, 20 feet from 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
Battery backup sump pump
Bridges the gap until the generator is running.
Amazon →
12-gauge extension cord, 50 ft
Pump to generator without a voltage drop.
Amazon →
Water alarm for the pit
Wakes you up before the carpet does.
Amazon →
Battery CO detector
Generator anywhere near the house means this is not optional.
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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