BoilerFaultCodes 30 40 50 60 70 80 [m m l l m m] High
Your boiler is unable to read the temperature of the water returning to it, so it has safely shut down to prevent damage.
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 (short circuit).
Typical repair cost £120-220 (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 l m m] — 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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