42E High
Your boiler has shut down because there is a confusing difference between the temperatures recorded at its internal sensors, often caused by poor water flow or a sensors reading incorrectly.
Technical description: Different temperature error
Typical repair cost: £90-250 (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 42E — no call-out fees, no surprises.
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Parts commonly replaced
- NTC Temperature Sensors
- Circulation Pump
- Main PCB
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