BoilerFaultCodes Green 'Flame' led
Your boiler is operating exactly as it should and is currently burning gas to heat your water or home.
Potterton Kingfisher MF RSL/CFL Fault codes & diagnostics
3 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Regular Natural GasLPG 12-30 kW 1994-2003 Discontinued
GC Numbers 41-590-5041-590-5141-590-5241-590-5341-590-5441-590-5541-590-5641-590-57
Replaced by: Promax SL
The fault code is already on your display
Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →
Just want the most common Potterton Kingfisher MF RSL/CFL faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes
All 3 documented codes
Tap any card for details
Red LED illuminated Your boiler has automatically shut down for safety because it has become dangerously too hot, or because the flue is blocked and exhaust gases cannot escape properly.
Your boiler has automatically shut down for safety because it has become dangerously too hot, or because the flue is blocked and exhaust gases cannot escape properly.
Parts commonly replaced
- Overheat Thermostat
- Flue Thermostat
- Flow Switch
- Pump
Red LED is 'ON' Your boiler has detected an internal fault or is not receiving a signal to start, and has locked itself out for safety.
Your boiler has detected an internal fault or is not receiving a signal to start, and has locked itself out for safety.
What to check first
- Check that your room thermostat and programmer are turned up and calling for heat.
- Ensure the gas supply to the property is turned on.
- Turn the boiler temperature control knob to the 'Off' position, wait 10 seconds, then turn it back to your desired setting to attempt a reset.
Parts commonly replaced
- Gas Valve
- Ignition Lead
- Printed Circuit Board (PCB)
- External Thermostat