Generac Gas pressure washer Parts — Browse All Models

What to do when water sprays out of the pressure relief valve on your Generac gas pressure washer

If the pressure washer runs for more than 5 minutes when the spray wand isn't in use, the water in the pump often overheats, causing the thermal relief valve to open and discharge hot water onto the ground. When the thermal relief valve opens, cool water enters the pump and cools the system. Once the pump has cooled, the thermal relief valve closes and the pressure washer operates normally. If the pressure relief valve purges constantly and doesn't close properly, replace it.

Common replacement parts for Generac gas pressure washers

• Unloader valve. When you let go of the trigger on the wand, the unloader valve opens to recirculate pressurized water to the pump, so the water won't overhead and damage the pump. If the unloader valve clogs or won’t open, the thermal release valve opens and sprays steamy water from the pump. Conversely, if the unloader valve won’t close, water pressure to the spray nozzle decreases drastically. If the pressure washer unloader valve isn’t working, replace it.
• Thermal relief valve. The thermal relief valve protects the pump from overheating. If the spray wand is unused for more than 5 minutes while the pump is running, the pressurized water heats up quickly. If the water gets too hot, the thermal relief valve opens to prevent damage to the pump. The thermal relief valve closes once the water temperature is cooler.
• Spray tip. The spray tip connects to the end of the spray wand. The spray tip restricts water flow and creates a spray pattern. An assortment of spray tips is usually provided with the pressure washer.
• Pressure hose. The pressure hose connects the pump to the spray wand. The pressure hose carries the pressurized water safely from the pump to the spray wand.