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Main Fault Codes

Select a fault code to see its meaning, common causes and how to fix it.

• E110 The E110 code on a Main (Eco Compact) boiler means the overheat safety thermostat has activated and shut the boiler… Read more →
• E119 The E119 fault code indicates that your Main boiler has detected water pressure that has dropped too low to operate… Read more →
• E125 The E125 code on a Main boiler signals a primary circulation fault — the boiler's PCB has detected that water is not… Read more →
• E133 The E133 fault code on a Main boiler indicates that the boiler attempted to light but failed to establish a flame,… Read more →