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Myson Boiler Fault Codes

6 fault codes · 16 models

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Myson was a British heating manufacturer known for their Marathon and Apollo boiler ranges. Very popular from the 1970s through to the early 2000s, particularly the floor-standing Marathon series. Myson boilers are simple in design with few electronic components, making them relatively easy to diagnose but increasingly hard to find parts for.

All Myson Fault Codes 6

Code Fault Severity Type View guide
FLUE SPILLAGE Flue Spillage Detector Tripped The flue spillage detector has activated, indicating combustion gases may be escaping into the room.… High Engineer View Guide
LOW PRESSURE Low System Pressure System pressure has dropped below minimum on sealed system models. Low DIY Check View Guide
NO IGNITION Main Burner Not Lighting The pilot is lit but the main burner does not fire when there is a… High Engineer View Guide
OVERHEAT High Temperature Lockout The boiler exceeded its safe operating temperature and the overheat thermostat has tripped. High Engineer View Guide
PILOT OUT Pilot Light Failure The pilot light has gone out or will not stay lit. On Marathon models this… High Engineer View Guide
PUMP FAULT Pump Not Running The circulation pump is not running. On Marathon models the pump is internal. High Engineer View Guide

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