Pressure Washer Coil Maintenance and Cleaning

The heating coil is the single most expensive component in a hot water pressure washer, and it’s the one most likely to fail if maintenance gets ignored. That’s why we offer a 5-year warranty on this component.

Scale buildup from hard water, soot accumulation from the burner, and general neglect will choke a coil’s performance long before the rest of the machine shows wear. 

The good news? Pressure washer coil maintenance isn’t complicated. Skipping costs you heat output, wasted fuel, and eventually a coil replacement that costs more than the preventive care would have over the unit’s entire life. We’ll walk you through the basics below.

As the #1 choice for an industrial pressure washer in San Antonio, our team handles coil service, descaling, and replacement parts for every major brand. So, give us a call or pay us a visit if you want to keep your equipment running its best for the long haul!

What Does the Coil in Your Hot Water Pressure Washer Do?

The coil is a continuous loop of steel tubing wrapped around the burner chamber. Cold water enters one end, passes through the heated coil, and exits the other end as hot water, typically between 180°F and 200°F depending on flow rate and burner output. 

The coil is what separates a cold water unit from industrial hot water pressure washers in San Antonio. It’s how these heated units clean 30-40% faster on oil and grease. Definitely an important component. 

Every degree of heat output depends on that coil transferring energy efficiently from the burner flame to the water inside. Performance drops when scale or soot get in the way of that transfer – even if the burner and pump are working fine.

Signs of Coil-Related Issues in Pressure Washing

Coil problems rarely show up in the form of a single dramatic failure. They build gradually, and the damage has been compounding for weeks or months by the time output is noticeably affected. Watch for these warning signs:

• Water isn’t reaching target temperature: The most common early sign. Scale is insulating the coil interior and blocking heat transfer if your hot water output feels lukewarm at settings that used to produce steam.
• Longer heat-up times: The burner runs longer before the outlet water reaches temperature. You’re burning more fuel for less result. Not viable long-term.
• Reduced water flow: Heavy scale buildup narrows the internal diameter of the coil tubing, restricting flow. The coil can clog entirely in severe cases.
• Visible scale at fittings: White or chalky mineral deposits around coil connections suggest the same buildup exists throughout the coil’s interior.
• Soot buildup on the coil exterior: Soot from the burner insulates the outside of the coil the same way scale insulates the inside. Both reduce heat transfer.

The coil may already need professional service if multiple signs are showing at once. We’re the #1 choice for pressure washer repair in San Antonio TX, even if it isn’t a Hotsy-brand unit. 

We can handle coil inspection, descaling, and replacement. Coil damage that goes unaddressed can also stress the pump, leading to costly pressure washer pump repair down the road. So, let’s talk prevention!

Preventing Pressure Washer Coil Issues in the First Place

Most coil failures trace back to water quality and maintenance neglect. There are a few simple things you can do to dramatically extend coil life in your pressure washer:

• Use the softest water available: Hard water is the main culprit behind internal scale. A water softener or filtration system upstream of the pressure washer will pay for itself in coil longevity alone if your water supply runs above 7-10 grains per gallon.
• Descale on a regular schedule: Mineral deposits build up over time, even with decent water quality. Run a pressure washer coil cleaner through the unit every 3-6 months (more often for hard water) to prevent buildup from restricting flow or blocking heat transfer.
• Don’t leave water sitting in the coil: Standing water speeds up scaling and can freeze in cold weather, cracking the tubing. Run the burner for 30 seconds with the trigger released after each use. This pushes remaining water through.
• Keep the burner clean: Soot on the outside of the coil insulates it just like scale on the inside. Inspect the combustion chamber every so often and clean soot build-up before it affects heating efficiency.
• Check the fuel nozzle: A worn or clogged fuel nozzle creates incomplete combustion, producing more soot as a result. Replacing the nozzle annually is cheap insurance against exterior coil fouling.

They say an ounce of prevention is worth a pound of cure, and the best thing you can do to keep your coil in tip-top shape is 1) addressing water quality 2) regularly using a pressure washer coil cleaner. So, how do you clean pressure washer coils correctly? 

Pressure Washer Coil Maintenance: How Do You Clean Pressure Washer Coils?

Descaling a pressure washer coil is simple. You’ll flush the interior with an acidic solution to dissolve mineral deposits without damaging the steel tubing. Here’s the general process:

1. Disconnect the water supply and relieve pressure: Turn off the machine, release the trigger to bleed residual pressure, and disconnect the inlet hose.
2. Prepare the descaling solution: Use a commercial pressure washer coil cleaner made for steel heating coils. White vinegar or citric acid works in a pinch, but purpose-built descalers are more effective and less likely to leave residue. Follow the manufacturer’s dilution ratio.
3. Circulate the solution through the coil: Connect a bucket or container of descaling solution to the coil inlet using a small transfer pump or gravity feed. Let the solution fill the coil and sit for the recommended dwell time (usually 30-60 minutes). Some technicians circulate it continuously for constant contact.
4. Flush thoroughly with clean water: Reconnect the water supply. Run fresh water through the coil for a few minutes to clear all descaling solution and dissolved mineral residue.
5. Inspect and test: Check outlet temperature against your baseline. If heat output hasn’t improved, the scale may be too severe for chemical descaling alone. The coil may need mechanical cleaning or replacement.

Don’t want to handle this yourself? Simply bring the unit into one of our shops or schedule a service call. We descale pressure washer coils regularly and stock replacement coils and pressure washer parts in San Antonio TX for every major brand if the coil is past saving.

Parting Thoughts on Pressure Washer Coil Maintenance

A well-maintained coil lasts years. A neglected one fails early and takes your hot water capability with it – costing you 30-40% of your cleaning speed on every job with oil and grease. 

Pressure washer coil maintenance is the highest-return preventive task you can do on a hot water unit. Descale on schedule, look at your water quality, and keep the burner side clean. Eventually, your coil WILL reach the end of its life. We carry replacements and can install in-shop or on-site. 

Or, it could just be a sign it’s time to replace your pressure washer – we can help you weigh repair against upgrading to a newer unit from one of the best commercial pressure washer brands on the market, Hotsy. Get in touch today to learn more!