AstralPool - 4-Way Reversing Valve for Heat Pump PM40 MD5 - 66069R0310

AstralPool – 4-Way Reversing Valve for Heat Pump PM40 MD5

This is the genuine AstralPool OEM 4-way reversing valve (position 30 in the official Fluidra exploded view) designed specifically for the AstralPool Heat Pump PM40 MD5 (WH000422). The 4-way reversing valve is a critical component of the refrigerant circuit: it redirects the flow of refrigerant through the system, enabling the heat pump to switch between heating and cooling modes. A faulty or failed valve will prevent the unit from changing modes or maintaining correct pool water temperature.

How It Works

Inside the valve, a solenoid-actuated sliding spool connects four refrigerant ports in two different configurations. In heating mode the valve routes hot refrigerant to the water heat exchanger; switching states reverses the cycle for cooling or efficient defrost operation. The solenoid is triggered by a signal from the heat pump’s control board, making the valve central to reliable, year-round operation of the PM40 MD5.

Compatibility

This valve is designed exclusively for the AstralPool Heat Pump PM40 MD5, identified by parent SKU WH000422. Always verify your unit’s model and serial number against the official Fluidra exploded view (position 30) before ordering. This valve is not confirmed to fit any other AstralPool heat pump model.

Why Genuine Matters

Using a genuine AstralPool replacement valve ensures correct port sizing, refrigerant compatibility, and solenoid rating for the PM40 MD5 refrigeration circuit. Non-OEM alternatives may cause refrigerant leaks, pressure imbalances, or control board faults that compromise both efficiency and warranty. Replacing with the original part keeps your heat pump performing to its rated specification.