BoilerFaultCodesYour boiler has detected a change in its internal electronic communication system or a new part, and it needs to be officially acknowledged before it will start again.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System configuration: new BUS device. New ISM detected.
What causes this fault?
This fault occurs when the boiler's main internal computer detects a new electronic component or a communication shift within its wiring system. It is most commonly triggered after a power surge, a recent part replacement, or if the main circuit board loses its stored memory settings and needs to be re-told which model it is operating.
This fault may be slightly more common after summer storms, as power surges from lightning or grid instability can disrupt the boiler's electronic memory.
DIY fix possible
Locate the 'Reset' button on the front control panel.Press and hold the 'Reset' button for approximately five seconds.Wait for the boiler to restart and check if the error code has cleared.
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 Fault 11 / 132 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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