Why does the new one still weep?

Almost always the expansion vessel — check pre-charge first before condemning the PRV.

Only fit WRAS-approved 3-bar PRVs to keep Worcester Bosch Greenstar 35i within its Gas Safe commissioning envelope.

Do I need to notify the manufacturer?

Only if the Worcester Bosch Greenstar 35i is in warranty — Worcester Bosch require log of any part swap for labour claims.

Fit a new 3-bar PRV on Worcester Bosch Greenstar 35i when water dribbles constantly from the outside discharge pipe.

Drain below the PRV, unscrew the old valve and fit new PTFE tape (10 turns clockwise).

On Worcester Bosch Greenstar 35i the PRV sits on the hydraulic block — torque to 25 Nm to avoid cracking the plastic manifold.

Refill the Worcester Bosch Greenstar 35i 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.

Why does the new one still weep?: Almost always the expansion vessel — check pre-charge first before condemning the PRV.
Any WRAS approval?: Only fit WRAS-approved 3-bar PRVs to keep Worcester Bosch Greenstar 35i within its Gas Safe commissioning envelope.
Do I need to notify the manufacturer?: Only if the Worcester Bosch Greenstar 35i is in warranty — Worcester Bosch require log of any part swap for labour claims.

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