Lawn Equipment Parts
Common Pressure-Washer Parts To Fix "Cannot Shut Off Pressure"
If you are unable to shut off the pressure from the wand, there may be an issue with the unloader valve that is stopping it from switching into bypass mode when the trigger wand is released. The unloader valve is designed to respond to the spike in pressure created when the trigger wand is released, and to divert the flow of water coming from the pump to bypass the pressure hose and flow back into the intake end of the pump. If the unloader valve fails to switch into bypass mode, water may continue to flow out of the trigger wand. This may also cause damage to the wand. If you are unable to shut off the pressure from your power washer, stop the engine and discontinue use immediately. The unloader valve should be removed and possibly replaced if found to be malfunctioning. The inability to stop the flow of high-pressure water from the wand can be dangerous and should be fixed before continuing to use the machine.
If you cannot shut off the water from the trigger wand and there are no known issues with the unloader valve, there is likely an issue with the wand itself. The trigger wand has a mechanism inside of it so that when the trigger is released, the flow of water is blocked. The spike in pressure created prompts the unloader valve to switch into bypass mode. If the seal that stops the flow of water through the wand is broken, water may continuously flow from the nozzle, as the unloader valve will not switch into bypass mode as it should. If you suspect your trigger wand is causing this issue, it should be replaced. Trigger wands can wear over time from the pressure they withstand, but should last for around 250 hours of operation. If bleach is regularly used in the power washer, this can cause internal parts of the wand to dry and crack, leading it to leak much more quickly. Any issues with the trigger wand should be addressed immediately, as the ability to shut off the flow of high-pressure water from the nozzle is very important and could be dangerous if lost.