Potterton Promax FSB 30HE Fault Codes

System Natural Gas 30 kW 2006-2008 Discontinued

GC Number: 41-591-93

Replaced by: Promax System HE Plus

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Most common fault codes

Code	Severity	Plain English	DIY
Burner On (Green Light)	Low	Your boiler is working normally and is currently firing to heat your radiators or hot water.	Yes
Condensate Pump (Green Light)	Low	Your boiler is currently pumping away waste water, which is a normal part of its operation and doesn't necessarily mean there is a fault.	Yes
FAN LOCKOUT	High	Your boiler's fan, which safely clears exhaust gases from the unit, has stopped spinning correctly and prevented the system from firing up.	Engineer
Flame Failure (Red Light)	High	Your boiler has tried to light but failed to stay on, meaning the system has shut down for safety until it is reset or repaired.	Yes
Mains On (Green Light)	Low	Your boiler is receiving electrical power and is ready to operate as normal.	Yes
On Off On Off	High	Your boiler has shut down because water intended for your drain is backing up and has triggered a safety sensor.	Yes
On Off On Off * * On On	High	Your boiler has shut down because it is unable to drain away the waste water it produces, causing a small internal reservoir to overflow.	Yes
THERMISTOR	High	Your boiler's internal temperature sensor has stopped sending a reliable signal, which means the system cannot safely monitor how hot the water is getting.	Engineer

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