How to Winterize a Pressure Washer
Water left in a pressure washer pump can freeze and crack it. Here's how to drain it, add pump protector and store it for winter, for electric and gas models.
The pump is the heart of a pressure washer, and it’s the part winter destroys. Water trapped inside expands as it freezes and can crack the pump housing, the seals and the fittings. Many pressure washer manuals warn that freeze damage isn’t covered by warranty.
If you’ll store your pressure washer anywhere that drops below freezing, like a garage or shed, winterize it. It takes about 15 minutes.
What you need
- Pump saver or pump protector (a non-toxic antifreeze and lubricant sold for pressure washers)
- A towel
- Fuel stabilizer, for gas models
Step 1: Drain the water
- Turn off the washer and the water supply.
- Squeeze the trigger to release pressure in the hose and wand.
- Disconnect the garden hose and the high-pressure hose.
- Turn the washer on its side or tip it so water drains out of the inlet and outlet. On an electric washer, you can turn it on for a couple of seconds with no water connected to push out what’s left; don’t run it longer, since pumps can be damaged by running dry.
- Drain the hose and wand, and coil them loosely.
Step 2: Add pump protector
- Screw the pump saver bottle onto the garden hose inlet.
- Squeeze the bottle until the protector comes out of the high-pressure outlet. On a gas washer, many directions say to pull the starter cord a few times as you squeeze to circulate it; check your engine’s instructions.
- Remove the bottle.
Pump protector keeps any leftover water from freezing and lubricates the seals so they don’t dry out.
Step 3: Gas engines only
- Add fuel stabilizer to the tank and run the engine for a few minutes so it reaches the carburetor, or run the tank dry, following your manual.
- Change the oil if it’s due.
- Check the spark plug and air filter.
Step 4: Store it
- Store indoors if you can, somewhere that stays above freezing.
- Clean and dry the nozzles and store them together.
- Store the hose loosely coiled, not kinked.
- Keep detergent tanks empty. Rinse them so soap doesn’t harden.
In spring
- Check hoses and O-rings for cracks.
- Connect the water and run water through the pump for a minute before turning it on, to flush out the protector.
- Check the oil on gas models.
Short answers
Can I use RV antifreeze instead of pump saver? Some owners do, but use what your manual recommends. Pump savers also lubricate seals.
Do I need to winterize an electric pressure washer? Yes. The pump freezes the same way on electric and gas washers.
What if my pump already froze? Let it thaw indoors, then check for leaks or cracks before using it. A cracked pump usually needs replacing.
Shopping for a new one? See the best electric pressure washers for home use.