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Reference · appliance watts

Appliance running and starting watts

A refrigerator uses about 700 running watts and surges to roughly 2,200 when the compressor starts. A furnace blower runs near 800 watts, a well pump about 1,000, a microwave about 1,000. The chart below lists running and starting watts for common home appliances, so you can size a generator or sanity-check a circuit. Every figure reads from the same data the generator worksheet uses, so the two never disagree.

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Refrigeration

Refrigeration: running vs. starting watts
Appliance Running (W) Starting (W) Motor?
Refrigerator or fridge-freezer 700 2,200 yes
Chest or upright freezer 500 1,500 yes

Water & sump

Water & sump: running vs. starting watts
Appliance Running (W) Starting (W) Motor?
Sump pump (1/3 HP) 750 1,500 yes
Sump pump (1/2 HP) 1,000 2,100 yes
Well pump (1/2 HP) 1,000 2,100 yes
Well pump (1 HP) 1,600 3,200 yes
Electric water heater 4,000 none no

Heating & cooling

Heating & cooling: running vs. starting watts
Appliance Running (W) Starting (W) Motor?
Gas furnace blower (1/2 HP) 800 2,350 yes
Electric space heater (1,500 W) 1,500 none no
Window AC (10,000 BTU) 1,200 1,800 yes
Window AC (12,000 BTU) 1,300 2,400 yes
Central AC (2 ton / 24,000 BTU) 3,800 5,800 yes
Central AC (3 ton / 36,000 BTU) 3,500 7,500 yes
Ceiling fan 60 70 yes

Kitchen

Kitchen: running vs. starting watts
Appliance Running (W) Starting (W) Motor?
Microwave (countertop) 1,000 none no
Coffee maker 1,000 none no
Toaster 1,200 none no
Electric range (one element) 1,500 none no
Dishwasher (hot / dry) 1,500 1,800 yes

Laundry

Laundry: running vs. starting watts
Appliance Running (W) Starting (W) Motor?
Washing machine 1,200 2,300 yes
Electric clothes dryer 5,500 6,750 yes
Gas clothes dryer 700 2,200 yes

Lighting & electronics

Lighting & electronics: running vs. starting watts
Appliance Running (W) Starting (W) Motor?
LED light bulb 12 none no
Incandescent bulb (60 W) 60 none no
LED TV (50") 100 none no
Laptop 60 none no
Wi-Fi router and modem 15 none no
Phone charger 10 none no

Comfort & medical

Comfort & medical: running vs. starting watts
Appliance Running (W) Starting (W) Motor?
Garage door opener (1/3 HP) 725 1,600 yes
Box fan 200 250 yes
CPAP machine 60 none no
How to read it

Running watts vs. starting watts

Running watts are what an appliance draws steadily once it is on. Starting watts, also called surge watts, are the brief spike a motor pulls in the first fraction of a second as it starts. When an electric motor first gets power its rotor is not yet turning, which looks electrically like a short circuit, so it pulls a large inrush current until it spins up. That is why a fridge that runs at 700 watts can jump to 2,200 for an instant.

Resistive and electronic loads have no rotor and no inrush, so their starting watts equal their running watts. That is why heaters, toasters, ranges, TVs, and lighting show no separate starting figure.

To size a generator, add the running watts of everything you need at once, then add the single largest starting surge on top. You do not add every surge together, because motors do not all start at the same instant. The generator worksheet does this math for you.

Caveats

Notes on specific rows

  • Well pump (1/2 HP): Submersible well pumps draw a big inrush. Check the pump's data plate; a specific unit can surge higher.
  • Well pump (1 HP): Running watts from the Franklin Electric AIM manual; the true locked-rotor inrush is higher. Check the data plate.
  • Electric water heater: A 240V resistive load. Only one element fires at a time, so do not double it. Most backup setups leave it off.
  • Gas furnace blower (1/2 HP): A gas furnace burns gas for heat but the blower motor needs backup power.
  • Central AC (2 ton / 24,000 BTU): Manufacturer figures for a 2-ton unit vary widely. Check the condenser's LRA on its data plate.
  • Central AC (3 ton / 36,000 BTU): Large startup surge (Generac lists a 3-ton at roughly a 100A locked-rotor draw). Check the data plate.
  • Microwave (countertop): Draws more than its cooking rating; manufacturer worksheets list about 900 to 1,100 W.
  • Electric range (one element): One 6-inch element. An 8-inch element runs about 2,100 W; the oven about 3,400 W.
  • Electric clothes dryer: The heating element sets the running watts; the drum motor adds the surge on top.
  • CPAP machine: CPAP draw varies a lot by model and humidifier setting, from about 7 W to 75 W. Treat this as a rough figure: read the wattage on your own device or its power supply, and confirm backup power with your doctor or equipment supplier before relying on a generator.
What we leave out

Figures we will not guess at

Some appliance figures have no clean manufacturer source, so rather than interpolate a number and present it as fact, we leave them off:

  • 2.5-ton and 3.5-ton central AC: no sourced wattage (and the two Generac documents disagree on the 2-ton figure by roughly double).
  • The exact draw of an 8,000 BTU window AC, and any 1/2 HP garage door opener: no manufacturer figure we could verify.
  • A whole electric range running every element at once: no published nameplate load, only forum guesses.

For any of these, read the data plate on your own unit. It lists the running amps and, for motors, the locked-rotor amps, which is the real number for your appliance.

Sources

Where these numbers come from

The figures are typical residential values from the wattage worksheets that generator makers publish (Honda, Kohler, Generac, Champion), with well-pump running watts from the Franklin Electric application manual and CPAP figures from ResMed's device documentation. The methodology page lists the full sourcing and explains what these estimates do and do not cover. Last reviewed July 2026.