The Worcester Bosch 87161066990 Main Harness is a genuine replacement wiring assembly that connects and routes electrical signals between key components within your boiler. This harness carries power and control signals to parts such as the PCB, sensors, actuators and safety devices, ensuring coordinated operation of ignition, fan, pump, valves and monitoring systems. A damaged or deteriorated harness can lead to intermittent faults, poor performance or complete control failure, so replacing it with the correct specification part is essential for reliable boiler function.

This main harness is compatible with Worcester Bosch Greenstar and Ri series boilers that specify part number 87161066990 in their internal parts documentation. To ensure correct fitment, always check the number on your existing harness or consult your boiler’s service information before installation, as wiring assemblies vary between models and configurations.

Supplied ready for direct replacement, the 87161066990 Main Harness integrates seamlessly with the boiler’s existing connection points and internal routing paths without modification. Choosing this genuine Worcester Bosch wiring harness helps restore proper electrical communication between components, supporting dependable operation and accurate control in compatible Greenstar and Ri boilers.