ProTool Build Troubleshooting Guide
ProTool Troubleshooting
Find the Problem. Fix the Issue. Get Back to Work.
The ProTool Skid and Trailer Troubleshooting Guide
Equipment problems happen. The important part is figuring out what's wrong without making the situation worse. Start with the symptom, work through the checks in order, and follow the fix. Most problems on a ProTool rig have a simple cause. If a fix is beyond what you're comfortable doing, email [email protected] and we'll walk you through it.
Last updated October 29, 2026
Before you work on anything: shut off the engines, let the burner and coil cool, squeeze the gun to relieve pump pressure, and turn off the battery disconnect.
Under warranty? Contact ProTool before you open up a pump, engine or burner. Opening some makers' components yourself can void their warranty.
Start here: the three most common calls
Soft wash pump losing prime or pulling air.
Check that the soap or SH tank isn't empty and that the pickup hose hasn't floated to the top of the tank. Then check the hose clamps and strainer O-rings.
Soft wash →High TDS on the pure water.
Replace the DI first, then check RO output.
Pure water →Something won't turn on.
It's usually the battery or a tripped breaker. Check the state of charge on the disconnect meter and charge it, then check the breakers: one for each remote, and one for all the electric reels.
Electrical →
Pressure washer
Honda GX690 engine, Centurion triplex pump, belt drive and BE diesel burner.
| Problem | Check first | Fix |
|---|---|---|
| Engine won't start | Battery charge, fuel level, oil level (the Honda low-oil shutoff stops it starting) | Charge the battery, add fuel or oil |
| Engine starts, then dies | Fuel tank vent blocked, old fuel, dirty fuel filter | Clear the vent, use fresh fuel, replace the fuel filter |
| Low or no pressure | Water supply and tank level, inlet strainer, worn or wrong nozzle, belt slipping | Restore water, clean the strainer, replace the nozzle, re-tension the belt |
| Pressure surges or pulses | Air in the inlet, low water supply, clogged inlet filter, worn check valves | Fix inlet leaks and supply; if it continues, the pump valves need service |
| Unloader cycling or pressure wrong | Pressure at the gun compared with the rated pressure; when the unloader was last checked | ProTool sets and tests the unloader before delivery, so it shouldn't need adjusting when new. Check it on the maintenance schedule; to reset it, follow How to adjust a pressure washer unloader valve the ProTool way |
| Water dripping under the pump | Seals and packings | Rebuild with a pump seal kit |
| Milky pump oil | Water in the oil | Stop running it; change the oil and have the seals checked |
| Belt squeals under load | Belt slipping | Re-tension so it deflects no more than about 1/2 in; replace if glazed or cracked |
| Pump runs hot in bypass | Gun closed too long | Most ProTool skids bypass back to the tank, so this isn't a concern. If yours dumps to the ground, don't sit in bypass more than 2–3 minutes |
| Downstream chemical not drawing | The tip: downstream only draws at low pressure. Then the injector screen and chemical hose | Use the right tip: a soap tip, or better, a ProTool shooter tip. Clean the injector screen; free or replace a stuck injector check valve |
Hot water burner
BE hot box with a Beckett 12V diesel burner. Diesel only. Never put gasoline in the burner tank.
| Problem | Check first | Fix |
|---|---|---|
| Burner won't light | Diesel level, burner switch on, thermostat turned up, battery charge, water flowing (the burner only fires with the gun open) | Fix the basics, then press the red reset on the burner control box once |
| Burner locks out again | Light on the control box | Do not keep pressing reset. Repeated resets flood the chamber with unburned diesel. Contact ProTool |
| Burner motor stops | Motor overload button on the side of the blower motor | Let it cool, press the overload reset, and find the cause (low voltage, jam) |
| Smoke or soot | Old or wet fuel, dirty fuel filter, worn nozzle | Drain water from the fuel filter, use fresh diesel, replace the nozzle |
| Water not getting hot | Thermostat setting, scale in the coil | Raise the setting; descale the coil |
When to call ProTool: the burner keeps locking out, the unloader won't hold pressure after resetting it, or the pump still pulses after you've fixed the inlet.
Soft wash
Comet P40 or BPX25 diaphragm pump on a Honda GX200, with the ProTool metering manifold. If the GX200 won't start or dies, use the engine checks under Pressure washer.
| Problem | Check first | Fix |
|---|---|---|
| Pump won't prime or pulls air | Empty soap or SH tank; pickup hose floated to the top of the tank | Refill, sink the pickup below the liquid |
| Still pulling air | Hose clamps, strainer O-ring seated, cracked fittings | Tighten or replace clamps, re-seat the O-ring, replace cracked fittings |
| Pulsing hose or uneven spray | Air leak on the suction side: hose clamps, fittings, strainer O-ring | Fix the leak |
| Low pressure or flow | Strainers clogged, wrong or worn tip, regulator setting | Clean strainers, check the tip, then check the regulator (below) |
| Regulator rattles or pressure creeps | Pressure setting | ProTool set-and-forget regulator: check the setting monthly; it shouldn't need adjusting. Stock Comet regulator: preset when ProTool tests the skid, but re-adjust it if you change guns or tips |
| Mix too strong or too weak | Metering valve settings, a sticking check valve, cracked bleach rinse valve | Reset the metering valves, free or replace the check valve, replace a cracked valve |
| Milky pump oil | Torn diaphragm | Stop running it; replace the diaphragms and oil |
| Pump runs but nothing comes out | Most often an empty soap or SH tank, or a large air leak on the suction side. Then a closed valve or blocked strainer | Refill the tank, fix the air leak (clamps, fittings, strainer O-ring), then open the valve or clean the strainer |
When to call ProTool: the pump still won't prime after you've checked the tank, pickup and every clamp, or the oil is milky.
Pure water (HydroPanel)
What normal looks like: pressure on the HydroPanel gauge while making water is 115–130 PSI on the HydroPanel 3.0 and 4.5, 80–90 PSI on the HydroPanel 2.0, and about 60 PSI on systems that run on tap pressure with no pump. RO output should be about 10% of your incoming TDS: with 300 TDS coming in, expect about 30 out of the RO. 34 is fine; 45 is not. On the HydroPanel 4.5, the auto flush runs for 60 seconds every 30 minutes; that's normal.
High TDS: work through it in this order
- Final output high? Replace the DI first.
- Still high? Check the RO output reading.
- RO output high? Check the membrane and housing seals and O-rings.
- Seals OK? Flush the RO for 15 minutes with the DI valve off.
- Still high after the flush? Replace the RO membranes.
| Problem | Check first | Fix |
|---|---|---|
| Pressure gauge not working or reading oddly | The gauge itself. Broken gauges happen more than you'd think and can send you chasing the wrong problem | Check the gauge before anything else. If it's stuck, reads zero while the system makes water, or the needle jumps, replace the gauge |
| Pressure below normal (115 PSI on 3.0/4.5, 80 PSI on 2.0) | Water supply, clogged pre-filters, pump inlet screen | Restore supply, replace pre-filters, clean the screen |
| Pressure above 130 PSI (3.0/4.5) | ProTool regulators hold 125–130 PSI, so a higher reading points to the regulator or the gauge | Contact ProTool; don't adjust the regulator yourself |
| Low pure water flow | Pre-filters, cold water (RO makes less in cold water), membranes | Replace pre-filters; expect less flow in winter; replace membranes if flow stays low |
| TDS high right after start-up | TDS creep after sitting | Flush 1–2 minutes with the DI valve off before each job |
| DI running out fast | RO output high, or flushing with the DI valve on | Fix the RO first; always flush with the DI valve off |
| Pump runs but no water | Water supply off, pump running dry | Restore water immediately; never run the pump dry |
| Auto flush not running (4.5) | Power and flush valve | It should flush 60 seconds every 30 minutes; contact ProTool if it doesn't |
When to call ProTool: pressure reads above 130 PSI, the auto flush stops, or TDS stays high after new DI, a 15-minute flush and checked seals.
Electrical and Skid Nexus remote
Most electrical problems are a low battery or a tripped breaker. Check the state of charge on the disconnect switch meter, then the breakers.
| Problem | Check first | Fix |
|---|---|---|
| Nothing turns on | Battery disconnect on, battery state of charge | Turn the disconnect on; charge the battery. A fully charged 12V battery reads about 12.7V; below about 12.2V, charge it |
| Everything on one remote is dead (its valves and indicator lights) | That remote's breaker. Each breaker feeds a remote, and the remote feeds its devices, so a tripped breaker shuts off the whole remote | Reset the breaker. If it trips again, don't keep resetting it; contact ProTool |
| Reel won't rewind | Battery charge; the reel breaker (all electric reels share one breaker, so if none of them work, check it first); hose snag | Charge, reset, clear the snag |
| Reel swivel or fitting leaking | The fitting where the reel connects to the manifold; swivel O-rings | Tighten the fitting on the manifold. If it still leaks, replace the swivel O-rings or the swivel |
| 12V valve won't open | Remote command and its indicator light, the valve's connector | Make sure the indicator light matches what you selected; check the valve's connector for corrosion. If everything on that remote is dead, it's the remote's breaker |
| Remote not responding | Remote battery, distance, pairing | Replace the remote battery, move closer, then re-pair (how to re-pair the Skid Nexus remote) |
Skid Nexus indicator lights
| Light | Soft wash | Pressure washer |
|---|---|---|
| Amber | Blinking: SH is flowing. Off: water is flowing | Blinking: downstream chemical tank is on. Off: water flush, or off |
| Green | Blinking: soap is flowing. Off: no soap | — |
If a light doesn't match what you selected, check the battery and the breaker, then re-pair the remote.
When to call ProTool: a breaker trips again right after you reset it, or anything smells hot or shows melted insulation. Don't work on energized wiring.
Freeze damage
A freeze is one of the most damaging things that can happen to a rig. Water expands as it freezes, and anything holding water can crack or break from the inside.
- Pressure washer pump: cracked manifold or head.
- Engines: possible internal damage.
- Soft wash pump: likely diaphragm and check valve damage.
- RO membranes: a frozen membrane is broken and must be replaced.
If your rig froze: don't start anything. Move it somewhere warm and let it thaw completely, then look for cracks, splits and leaks before you run water through it. Contact ProTool before you run it. Freeze damage is not covered by the warranty, so follow the winterizing steps in the maintenance guide before the first cold night.
Keep it from happening again
Most of these problems trace back to a skipped check. The ProTool Skid and Trailer Maintenance Guide has the daily checklists and service schedule, and the ProTool Warranty explains what's covered.
Troubleshooting FAQ
Why is my ProTool soft wash pump losing prime or pulling air?
Most often the soap or SH tank is empty or the pickup hose has floated to the top of the tank. If the tank and pickup are fine, check the hose clamps, fittings and strainer O-ring on the suction side for an air leak.
Why is the TDS high on my ProTool HydroPanel?
Work through it in order: replace the DI first, then check the RO output reading. If the RO output is high, check the membrane and housing seals, then flush the RO for 15 minutes with the DI valve off. If it's still high after the flush, replace the RO membranes.
What TDS should my HydroPanel RO output read?
RO output should be about 10% of your incoming TDS. With 300 TDS coming in, expect about 30 out of the RO. A reading of 34 is fine; 45 is not.
What pressure should my ProTool HydroPanel run at?
While making water, the HydroPanel 3.0 and 4.5 run at 115–130 PSI and the HydroPanel 2.0 runs at 80–90 PSI. Systems that run on tap pressure with no pump run at about 60 PSI.
Why won't anything on my ProTool rig turn on?
It's usually the battery or a tripped breaker. Make sure the battery disconnect is on and check the state of charge on the disconnect meter. Then check the breakers: one for each remote, and one for all the electric reels.
Why won't the burner on my ProTool hot water skid light?
Check the diesel level, that the burner switch is on, the thermostat is turned up, the battery is charged and water is flowing (the burner only fires with the gun open). Then press the red reset on the burner control box once.
How many times can I press the burner reset button?
Once. If the burner locks out again, don't keep pressing reset. Repeated resets flood the chamber with unburned diesel. Contact ProTool instead.
Why isn't my downstream injector pulling chemical?
Downstream injectors only draw at low pressure, so use the right tip: a soap tip, or better, a ProTool shooter tip. Then clean the injector screen and free or replace a stuck injector check valve.
Why is the oil in my pump milky?
Milky oil means water is getting into the oil. On a pressure washer pump it usually means worn seals; on a Comet soft wash pump it usually means a torn diaphragm. Stop running it and change the oil, then have the seals or diaphragms checked.
What should I do if my ProTool rig froze?
Don't start anything. Move it somewhere warm and let it thaw completely, check for cracks, splits and leaks, and contact ProTool before you run it. Freezing can crack pump manifolds, damage engines and soft wash diaphragms, and ruins RO membranes. Freeze damage is not covered by the ProTool warranty.
How do I re-pair the Skid Nexus remote?
Replace the remote battery and move closer first. If it still doesn't respond, follow the ProTool video on re-pairing the Skid Nexus remote.
When should I contact ProTool support?
Email [email protected] when a breaker trips again right after a reset, the burner keeps locking out, HydroPanel pressure reads above 130 PSI, or a problem remains after the checks in this guide. Include your order number, what you're seeing, and a photo or video.
Still stuck? Email us with your order number, what you're seeing, and a photo or video. We'll help you find the problem and get the right part.
Keep it running with the ProTool Maintenance Guide. Coverage questions? See the ProTool Warranty.