BoilerFaultCodes 10.iv High
Your boiler is struggling to move heat away from its internal workings, causing it to quickly turn on and off as it tries to protect itself from overheating.
Call an engineer soon
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Rapid cycling high/low or high/low/off - Blocked heat exchanger
Typical repair cost £150-300 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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 10.iv — no call-out fees, no surprises.
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Chaffoteaux Sterling FF 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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