Worcester Bosch Return Unit Assembly No Motor 87186880960

The Worcester Bosch 87186880960 is a return unit assembly supplied without its motor. It sits within the diverter valve and hydraulics group of the appliance, where it forms part of the manifold arrangement that controls the movement of water through the return path of the boiler.

The assembly is used across the Greenstar Compact system range, including the 27i and 30i variants in both natural gas and LPG formats. Because the motor is not included, this unit is the correct choice where the hydraulic body itself has failed but the existing drive motor is still serviceable.

• Radiators warming when only domestic hot water is being drawn, or no heating when the heating circuit is called for.
• Domestic hot water running hot and cold, or staying cold while the heating circuit remains hot.
• The boiler failing to move between heating and hot water modes, often accompanied by a lockout or a fault code on the display.
• Water weeping from the hydraulic block or around the body of the return unit.
• The motor running but the internal valve not moving, indicating a seized or damaged assembly.

• Check the GC number and appliance model against the compatibility list, as the same part number is used across several Greenstar Compact variants.
• Cross-reference alternative part number 1031227 when checking older documentation or supplier listings.
• Inspect the seals and O-rings around the hydraulic block while the assembly is removed and renew any that are perished.
• This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.