E35 High
Your boiler is struggling to detect a stable electrical signal from the mains power supply, causing it to shut down as a safety precaution.
Technical description: Mains supply frequency incorrect – may be a problem with the power supply
Typical repair cost: £100-£350 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Protect yourself from future repair bills
A boiler cover plan would cover faults like E35 — no call-out fees, no surprises.
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Parts commonly replaced
- Printed Circuit Board (PCB)
- External power supply/wiring
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