BoilerFaultCodes 7.iii High
Your boiler has lost the air pressure needed to run smoothly, causing it to release excess water to prevent unsafe pressure levels within the system.
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: Safety valve discharges - Vessel lost air charge
Typical repair cost £150-250 (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 7.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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