BoilerFaultCodes 30 40 50 60 70 80 [m m l m l l] High
Your boiler has lost the ability to read the temperature of the water returning to it, so it has safely shut down to prevent 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: Central heating return 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 30 40 50 60 70 80 [m m l m l l] — no call-out fees, no surprises.
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Chaffoteaux Minima HE 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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