Pressure Control Valve - Complete Set

Complete unloader control piston assembly together with the pressure regulating knob. A ready-to-install set replacing the entire pump working-pressure regulation mechanism.

Application

The assembly handles working-pressure regulation and acts as the water circuit safety with the gun closed – when the trigger is released, excess water is redirected back into the low-pressure circuit instead of generating an uncontrolled pressure rise in the pump. The knob allows smooth adjustment of the working pressure value without dismantling the unit.

Symptoms – when to replace

• Working pressure cannot be adjusted with the knob, or it changes on its own during operation.
• Water leaking from the unloader housing near the knob or control piston.
• The pump jerks noticeably when the gun is closed or opened, despite sound plunger seals.
• The regulating knob is loose, sticks, or fails to transmit movement to the internal mechanism.

How to choose the right part

Selection is based on reference number 44209 – confirmed specifically for the WS 1000 TS, therm 895-1 and therm 1165-1. Other WS models may require a different number of the same assembly type (43444), so substituting without confirming the exact model can result in a mismatch.

When ordering for a WS model, confirm exactly whether it's the 1000 TS variant or another one (e.g. 800 TS/1200 TS) – valve blocks can look similar externally but require different assemblies.