The ST265 unloader valve is an important component in pressure washer systems that are used for heavy-duty applications. Its main purpose is to regulate and control the water pressure and flow, thereby protecting the pump and other components from damage. The valve works by monitoring the pressure in the system and opening or closing depending on the set pressure point. When the pressure exceeds the set point, the ST265 unloader valve opens, allowing water to bypass the pump and return to the water source. This action maintains a consistent flow of water and protects the pump from overpressure, which can cause damage and decrease its lifespan. Additionally, the ST265 unloader valve has an adjustable bypass pressure setting that enables operators to customize the valve to meet the specific needs of their application. Overall, the ST265 unloader valve plays a critical role in maintaining safe and efficient pressure washer systems for heavy-duty applications.