UK trade guideBoiler Spares 5 min readUpdated 11 July 2026

How to Replace the Pcb on a Worcester Bosch Greenstar 32i (UK)

Step-by-step UK guide to replacing the printed circuit board on a Worcester Bosch Greenstar 32i. Part numbers, torques, commissioning.

Worcester Bosch

The part

Replace the main control PCB — the most common cause of no-heat, no-DHW and intermittent lockouts on Worcester Bosch Greenstar 32i.

Isolate safely

Isolate at the fused spur and lock off. Discharge any residual mains voltage before touching connectors.

Fit and commission

Photograph every plug and its position on the Worcester Bosch Greenstar 32i PCB before unclipping — connector positions differ subtly across firmware revisions.

Recommission checklist

Refill the Worcester Bosch Greenstar 32i to 1.2 bar cold. Bleed high-point radiators and the internal AAV.

Run a full flue-gas analysis after 15 minutes. Log the reading against the OEM commissioning envelope in the Benchmark book.

Frequently asked questions

PCB part number location?
On Worcester Bosch Greenstar 32i the PCB label is on the top-right of the board, printed as an 8716-series code. Match every digit.
Do I need to re-parameterise?
Yes — enter the correct boiler model code in the service menu after fitting so the ignition curve, fan speed and gas rate match.
Do I need to notify the manufacturer?
Only if the Worcester Bosch Greenstar 32i is in warranty — Worcester Bosch require log of any part swap for labour claims.
Shop the spares

Browse boiler spares14,820 live parts.

View Boiler Spares