The 6 most common faults
01
02
DRY-FIRE Engineer
Flow & Return reversed, system not full of water, or pump/flow switch fault
Full guide for DRY-FIRE03
IGNITION LOCKOUT Engineer
No gas at gas valve, incorrect gas supply, blocked flue, blocked condensate trap, damaged probe, or faulty PCB
Full guide for IGNITION LOCKOUT04
OVERHEAT LOCKOUT Engineer
Stat fault, thermistor resistance out of range, or damaged combustion chamber door seal
Full guide for OVERHEAT LOCKOUT05
06
Call a Gas Safe engineer if…
- You can smell gas or see signs of a leak
- The Potterton shows an Emergency or High severity code
- The boiler keeps locking out after repeated resets
- You've tried the DIY checks and the fault hasn't cleared
- There's visible water leaking from the boiler
- The flame is yellow or orange instead of blue
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