BoilerFaultCodesYour boiler's internal computer has encountered a software glitch or a communication error that is preventing it from running properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal error
What causes this fault?
This fault occurs when the boiler's main control board experiences a software crash or fails to communicate with the internal sensors correctly. It is often caused by a sudden electrical surge, loose internal wiring, or a critical hardware failure within the printed circuit board itself.
DIY fix possible
Locate the reset button or turn the selector switch to 'R'Hold for 5 seconds and then releaseWait 2-3 minutes to see if the boiler restarts normally
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 E135 — no call-out fees, no surprises.
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Baxi GA Range 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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