BoilerFaultCodesYour boiler's main control computer is unable to communicate with its internal plug-in components, meaning the system cannot safely start up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Module not detected.
What causes this fault?
This fault occurs when the boiler's central brain fails to recognize or connect with the essential control module plugged into it. It is usually caused by a loose internal connection, a sudden electrical surge, or a component failure on the main circuit board that prevents data from flowing correctly.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like AC — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Worcester Bosch Greenstar 30HE 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.
Affiliate links — we may earn a commission at no extra cost to you.