Top 5 pressure washer problems to avoidTips to keep your pressure washer working well

06 November 2015

a leaking pressure washer

The most common pressure washer fault is water leaking from the body

A unique Which? survey has revealed the five most common faults that affect pressure washers, so we can help you to avoid them, too. 

We asked over 6,400 Which? members about the reliability of the garden machinery they had bought in the past 10 years. 

Nearly two thirds of Which? members own a pressure washer, and around a quarter have bought one in the past five years. 

If you're thinking of buying a pressure washer then you'll want a quick machine that's also easy to use. Choose the right one for you from our Best Buy pressure washers.

Here's a round up of the top five problems Which? members had encountered with their pressure washers and our advice on how to avoid them.

1. Water leaks from within the washer

Likely cause

This most common fault frequently appears after a pressure washer has been left idle over the winter and is often caused by water in the pressure washer freezing, expanding and splitting plastic components. 

An old and worn-out pump can also be the cause. 

How to avoid

Drain your pressure washer before you store it for the winter - check the manufacturer's instructions for how to do this. Do not allow your pressure washer to freeze by storing it in a frost-free place.

It is possible to buy replacement parts for the plastic components and pumps of some pressure washers - check the manufacturer's website for further details.

2. Lance fails

Likely cause

If there's no water coming out of the lance it might be that the nozzle is blocked.

If the lance itself is leaking this is probably due to splits in the plastic or failures of the seals caused by wear and tear. 

How to avoid

Always check that your lance and nozzles are assembled properly before turning on the trigger to avoid straining the seals between them.

Avoid dropping your lance on the floor while you are using it and always check that the nozzles are free of debris. If your pressure washer has storage slots for the lance and nozzles, use these when you are cleaning instead of propping the lance on the floor.  

3. Washer loses pressure 

Likely cause

There can be a number of problems that cause this symptom, such as a blocked nozzle or water inlet, inadequate water supply, air in the inlet water supply hose or the pump.

How to avoid

If the pressure is pulsing it's worth checking that the water supply is fully turned on and that the hose supplying the pressure washer is not squeezed or kinked first. Then clean the water filter. To get rid of air run the pressure washer with an open spray handle and nozzle at low pressure until regular working pressure resumes.

If the pressure is steady but low it can indicate a worn stop/start valve - squeeze the trigger five times in quick succession to get it working again. Otherwise it might be a worn nozzle, which should be replaced.

4. Seals fail

Likely cause

Again, this is commonly caused by frozen water damage or wear and tear. 

How to avoid

Avoid storing your pressure washer where it can freeze.

Seals can be replaced in some cases, so check with the manufacturer.

5. Pump fails

Likely cause

Frozen and cracked pump components are the chief suspect here, but another culprit could be running the pump without the water flowing, or ignoring other problems that cause the pressure washer to run incorrectly.    

How to avoid

Store the pump correctly and make sure that the water is turned on and at adequate pressure before running the pump. Takes steps to remedy a pulsing pressure washer.  

To find out which brand makes the most reliable pressure washers, visit our pressure washers review.

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