701 High
Your boiler has detected a technical fault with its internal temperature sensors, which is preventing it from heating your home or water safely.
Technical description: E-Combi EvoE-System EVOClas HE evo combiClas he evo system
Typical repair cost: £120-250 (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 701 — no call-out fees, no surprises.
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Parts commonly replaced
- Flow NTC Temperature Sensor
- Return NTC Temperature Sensor
- Internal Wiring Harness
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