BoilerFaultCodes 9.iii Emergency
Your boiler is overheating because it is burning more gas than it can safely process, causing the internal system to shut down to prevent damage.
Act immediately
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Excessive temperature rise across boiler - Gas rate too high
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 9.iii — 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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