BoilerFaultCodes 9 High
Your boiler is struggling to detect the temperature of the water used for your taps and shower, which means you will likely have no hot water until it is fixed.
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: DHW thermistor, faulty, Open circuit
Typical repair cost £120-200 (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 — no call-out fees, no surprises.
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Chaffoteaux Talia Green 25 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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