Setting up a heated pressure washer on a trailer can make your cleaning setup mobile, efficient and ready for tough jobs. But getting it right isn’t just a matter of bolting on a few parts. You’ll need to think about water storage, trailer size, weight distribution, power supply and how everything fits together. If you’re planning to use this setup for commercial work, farming or industrial cleaning, here’s what you’ll need to get started.

 

How to Install a Hot Water Pressure Washer on a Trailer

Understanding how to install a hot water pressure washer on a trailer starts with planning your layout. You’ll need enough space for the core components, adequate weight distribution and secure mounting systems to keep everything in place during transport. A well-planned build can save hours in the field.

 

Heated Pressure Washer Components to Include

 

1. Hot Water Pressure Washer Unit

Start with a reliable heated pressure washer. These units typically run on diesel or petrol and come equipped with a built-in burner to heat the water. Choose a model that matches your pressure and flow rate needs. Cheaper cold-water washers with add-on heating coils usually don’t cut it for demanding jobs. Look for a purpose-built hot water unit with a good warranty and support options.

 

2. A Suitable Water Tank

Your washer won’t get far without a tank. Most users go for tanks between 300L and 1000L, depending on how often refills are possible and how long jobs take. The larger the tank, the heavier your trailer. For help figuring out your tank-to-trailer ratio, take a look at our breakdown on the best hauling water trailer size for your setup.

 

3. Hose Reels That Fit the Space

Hose reels make setup and pack-up much quicker. But with limited trailer space, it can be tricky to fit everything in. One question we often get is: is it safe to stack hose reels on a pressure washing trailer? With the right support brackets and balanced layout, stacked reels can work well. Just make sure the combined weight doesn’t shift your centre of gravity too high.

Also think about your hose reel configuration. If you’re working with a smaller trailer, consider a custom hose reel setup for small trailer use. Grouping reels vertically or using fold-away systems can help maximise the limited footprint.

 

4. A Reliable Power Source

Many hot water units are self-contained. But if yours needs extra power for accessories or an electric start, you’ll need a generator or battery setup. Make sure whatever you choose is secure and well ventilated. Poor ventilation increases fire risk, and loose batteries can be damaged on rough tracks.

 

5. Secure Mounting Frames and Skids

Everything from your pressure washer to your tank should be fixed in place. It’s not enough to strap things down with a few ratchet ties. Use welded steel frames or skid mounts to keep equipment steady. Trailers experience plenty of vibration and movement on the road, and loose gear is a hazard for both people and equipment.

 

Trailer Choice and Weight Management

Your trailer is the backbone of the setup. Load too much on a trailer that isn’t rated for it and you’re risking damage, fines and safety issues. So how do you work out what you need?

Start by adding up the approximate weights:

 

  • Pressure washer unit: 60 to 150 kg
  • Full water tank (e.g. 1000L): up to 1000 kg
  • Fuel: 20 to 40 kg
  • Hose reels, tools, frame: 50 to 100 kg or more

 

That’s already over a tonne. And that doesn’t include the trailer’s own weight.

Make sure your trailer’s GVWR (Gross Vehicle Weight Rating) covers the full load. For builds like this, a dual-axle trailer is often the safest choice. It provides more stability and load capacity, which is especially important for a full hot water pressure washer trailer setup.

 

Weight Distribution and Balance

Position your heaviest items over the axles. Don’t lump everything at the back or on the drawbar. Poor balance causes trailer sway, tyre wear and difficult towing. It also makes cornering harder.

Aim to keep the drawbar weight around 10 to 15 percent of the total trailer weight. Too light and you’ll have sway. Too heavy and your towbar will be overloaded.

 

Accessories That Make Life Easier

A few extras can make a big difference:

 

  • Toolboxes or lockable storage for chemicals, fittings and small tools
  • Tap connections or filters for water sources that vary in pressure or quality
  • Side rails or ladder racks for carrying extra items
  • Electric brakes for trailers over 750 kg ATM

 

Each add-on affects your trailer load. Always review your weight distribution again once they’re fitted.

 

Ongoing Trailer Maintenance

Maintenance is non-negotiable. If you’re using your trailer often, keep an eye on the basics:

 

  • Check wheel bearings every six to twelve months
  • Tighten wheel nuts after the first 50 km
  • Keep tyre pressure at spec
  • Replace cracked hoses or worn seals
  • Protect all electrical components from water and vibration

 

Good care extends the life of your gear and avoids costly surprises down the track.

 

Build a Setup That Works for You

Every pressure washing job is different. Some need longer hose lengths. Others rely on extra-large tanks. But what all successful trailer builds have in common is thoughtful planning, secure mounting and the right heated pressure washer components.

Still figuring out the details? At Coastmac, we’ll help you create a setup that’s right for your jobs. Whether it’s a single-axle rig or a customised dual-axle trailer with everything bolted on, we’ve got the parts, advice and practical experience to get it right.