What to do if the thermal relief valve is open on my Hyundai HYW4000P?
- TTimothy GibbsSep 22, 2025
If the thermal relief valve on your Hyundai Pressure Washer is open and discharging water, it could be due to the water temperature being too high. Use cool water only. It can also happen if the pump has operated for more than 3 minutes without pulling the trigger. Pull the trigger for at least 30 seconds every 3 minutes.





