BoilerFaultCodes 10.i Medium
Your boiler is struggling because it cannot pump enough water through the system, causing it to rapidly turn on and off to protect itself.
Book a service
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Rapid cycling high/low or high/low/off - Low water flow rate
Typical repair cost £120-250 (including labour)
DIY fix possible
Check your central heating pressure gauge and top it up to 1.5 bar if lowEnsure all radiator valves are fully openCheck that your external pump speed setting has not been turned down
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.i — 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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