BoilerFaultCodesMyson C551A Fault Code
The Myson C551A fault code means: your boiler has detected an issue with the sensor that confirms the burner flame is lit, causing it to shut down for safety reasons.. It appears on 1 Myson model in our database.
Technical description: mechanical fame detector
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 →Avoid the next call-out bill
A cover plan would handle faults like C551A: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
Myson models that show the C551A fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Myson C551A fault code information on this page is sourced and cross-checked against the official Myson service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026