BoilerFaultCodes D.44 Medium Warning
Your boiler's electronic system is struggling to correctly detect the flame signal, which could lead to it locking out for safety.
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: Digitised ionisation – potential error
What causes this fault?
This fault occurs when the boiler's internal computer receives an unstable or unexpected signal from the flame sensing components. It usually happens because the sensor that monitors the flame is dirty, worn out, or the electrical connection between the sensor and the main control board has become weak.
Typical repair cost £120-280 (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 D.44 — no call-out fees, no surprises.
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