How to Winterize a Pressure Washer?

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How To Winterize A Pressure Washer Get Your Pressure Washer Ready For Winter With Our Pressure Washer Winterize Guide

It doesn’t matter whether you own an electric pressure washer or a gas unit. It’s equally important that you know how to store it properly. Firstly so it still works in spring and secondly so that you can take advantage of your unit’s warranty, which could be void if not winterized correctly.

How To Winterize A Pressure Washer

Knowing how to store a pressure washer will ensure that yours continues to work the way it should for as long as possible. It means there won’t be any issues when you come to use it when you take it out of storage.

Once summer passes, it is vital to winterize your pressure washer. Why is this important, you ask? Well read on, and I’ll explain exactly why and take you through the essential steps to winterize your unit.

Winterizing a Pressure Washer – Why Is It Essential?

You’ve heard that you should winterize your pressure washer, and perhaps you are wondering why it’s such an important task? When you aren’t using your pressure washer, it’s internal components can be affected by the cold temperatures—these cold temperate wreck havoc on the internal parts, especially the seals.

Because of this, you need to ensure that the seals are lubricated so that they stay in good condition throughout winter.

Can You Leave a Pressure Washer Outside?

It doesn’t matter whether you own a portable pressure unit or something bigger. You need to ensure that you store it correctly, so it doesn’t suffer damage, and it’s seals, etc, stay intact. Hopefully, you are now wondering if leaving a pressure washer outside is a good idea at all.

Well, it’s not. You should never, under any circumstance, store your pressure washer outside. If it rains, the rain can damage the unit. While these machines expel water, they may not be entirely waterproof. Portable units test to be covered in plastic, but the larger ones expose some of the metal parts.

These metal parts can suffer corrosion if left out in the elements for a long time. Pressure washers aren’t designed to resist heavy rain or huge amounts of water, so it makes sense to store your pressure washer in an enclosed space where it will remain dry.

If you’ve read your pressure washer user manual, you may have noticed that it states not to use the pressure washer to clean itself, and that’s rather self-explanatory.

Can Pressure Washers Get Wet?

While yes, your pressure washer can handle some water, it’s not recommended, even more so if you are considering leaving it out in the rain or using a hose or pressure washer to clean it.

Can Pressure Washers Get Wet

That said, some pressure washers are constructed to be much more resistant and capable of handling a higher level of abuse compared to other models. These can handle being splashed by water and may not suffer any damage. These, however, tend to be the more heavy-duty units.

To see how much water and dust your pressure washer can handle, you can check out its IP rating. This is a standardized number that tells you exactly how robust an item is against water and dust. However, I suggest that regardless of how high your IP rating may be, you shouldn’t use these where the ground is wet or if it’s raining. Especially if it’s an electric model.

The electric models come with a risk of you electrocuting yourself if care isn’t taken. This isn’t the case with a gas-powered unit, which makes them the ideal choice to use in damp conditions.

If your user manual doesn’t state an IP rating, then you should assume that your pressure wasn’t cannot get wet.

How to Winterize a Pressure Washer?

You’ve paid good money for your pressure washer, so you want to ensure it’s kept safe during winter. How do you winterize it to ensure that it works as good as it does today next spring? Here are the steps I suggest you take.

1. Gas Pressure Washers

Let’s start with gas pressure washers. These units tend to be more robust than their electric counterparts. These are capable of resisting damp conditions, but don’t let that give you a false sense of security. These shouldn’t be left to sit outside subject to the elements.

Here’s how to prepare your gas pressure washer for winter.

  1. Protect the engine – If you believe that you won’t need to use your gas unit for a month or so, then the engine needs to be protected. Firstly get some fuel stabilizer; gasoline doesn’t do well when it goes stale, and fuel stabilizer helps with this and add this to your gas tank.
  2. Run the engine with Fuel Stabilizer – Once you’ve added the fuel stabilizer to the gas tank, ensure that you’ve hooked your pressure washer up as if you were going to use it, so water flowing in from a hose, run the engine for around 2 minutes or however long the fuel stabilizer suggests to allow the stabilizer to circulate through the engine.
  3. While the engine is running – We want to flush the system. Fill a bucket with clean water and place your detergent feed tube into the clean water. If you don’t have a siphon tube system, fill the detergent tanks with clean water. Run the unit by pulling the trigger on the spray wand, I suggest attaching a low-pressure nozzle beforehand. Allow the water to flow through the system for a few minutes to ensure that no cleaning solutions are lurking in the pump.
  4. Remove Water and Cleaning Solutions – We’ve flushed the system, but now you should remove any water from within the unit, make sure that the pump is free of water, and that there aren’t any detergents or other cleaning solutions in the system at all.
  5. Use Anti-Freeze, aka “Pump Saver” – Add some pump saver to the pump inlet. This is very important if you expect the temperatures to drop well below freezing.

2. Electric Pressure Washers

Electric pressure washers are much easier to winterize, and this is how to do it.

Clear out the pump system – Pour some tap water into a pump and take the hose for the detergent suction and place it into the bucket, if you don’t have a siphon tube then fill the detergent tanks with clean water, you may need to do this a few times to remove all signs of detergent. Turn the unit on and pull the trigger, allowing water to spray out. This may take a few minutes. Once done, remove the hose.

Store the washer – Make sure to store the pressure washer indoors, in a place that isn’t damp. You want to store your unit in a warm place to prevent the unit from freezing. If this isn’t possible, then add some pump saver.

Adding pump saver – This isn’t as easy as it is with a gas unit, but the way I’ve done it is to feed it in from the detergent inlet. Though the easiest option is to store the pressure washer indoors.

Where Should You Store the Pressure Washer?

Where Should You Store The Pressure Washer

Pressure washers are happiest when you store them in a warm, dry place during winter.

If you have a basement or even a garage, then these can be the ideal place to store your pressure unit.

Though you need to ensure that where you store them is clean and dry and also ideally warm. There’s no point storing your pressure washer in your garage if it’s likely to go below the freezing point.

I suggest if you can to bring your pressure washer indoors, this may not be possible with a gas unit, but electric models can sit in a cupboard under the stairs.

Closing thoughts

Properly winterizing your pressure washer will ensure that your pressure washer lasts a long time and doesn’t incur large repair bills. If the unit is electric, then it will prevent you from having to buy a new one as these aren’t usually built for repair.

Make sure to follow the methods I’ve shown above before storing your pressure washer during the cold season.

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Adam White is the founder and chief editor at He has years of experience from years of Gardening, Garden Design, Home Improvement, DIY, carpentry, and car detailing. His aim? Well that’s simple. To cut through the jargon and help you succeed.