F34 High
Your boiler is not receiving enough electricity from the mains supply to operate its electronic components safely.
Technical description: Supply voltage under 170v – electric supply error
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 F34 — no call-out fees, no surprises.
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Parts commonly replaced
- Printed Circuit Board (PCB)
- External Electrical Supply Wiring
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