BoilerFaultCodesYour boiler's internal pump or motor is not receiving power or has stopped working, meaning it cannot circulate heat through your system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty motor or electrical supply to motor
What causes this fault?
This fault occurs when the boiler's internal pump fails to move water, which prevents heat from leaving the unit and reaching your radiators. The most common reasons are a physical blockage or mechanical failure within the pump motor itself, or a communication issue where the main control board is unable to send electricity to the pump.
This fault is frequently seen at the start of autumn when systems are turned back on after sitting idle all summer, which can cause the pump internal parts to seize up.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 73 — no call-out fees, no surprises.
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Worcester Bosch Greenstar Utility 18/25 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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