Ideal Logic System IE Gen 2 fault F12
Pump rotor blocked
Gas boilerWhat it means
Fault indicating the pump rotor is blocked/seized.
Likely causes
- Blockage in pump rotor
- System not filled/vented
- Closed valves
- Excessive flow/return differential
- Pump not rotating freely
- Isolation valves closed
- Pump not operating
- Radiator valves closed
- System blockages
- Pump not operating (wiring fault or pump failure)
- System blockage restricting flow
- Thermistor fault requiring replacement
- Faulty or failed return thermistor requiring replacement
Where to start
- Verify boiler and CH system filled with water
- Verify all isolation, system filter and radiator valves are open
- Measure flow/return differential across boiler
The full answer, free
- 35 more checks in order
- The readings and component tests from the manual
- How to put it right, step by step
- The manual page for this fault (page 49), right under the answer
Safety: Isolate gas and power before you open the case. If you have been into the gas side, do a tightness test, and a combustion and flue check before you hand back. Gas Safe (UK) or RGI (Ireland) work only.
From the Ideal manual for the Logic System IE Gen 2. Check the model on the data plate before you order parts.
Other Ideal Logic System IE Gen 2 fault codes
- F02Flame loss
- F03Fan fault
- F04Flow thermistor fault
- F05Return thermistor fault
- F06Outside sensor fault
- F09PCB fault
- F0DLow water flow / low water pressure
- F0TRoom thermostat fault
- F0UFlow/return differential greater than 50°C
- F10Spark generator fault
- F13Pump fault
- F15Pump fault
- F16Gas valve fault
- F17Pump fault
- L01Flow temperature overheat lockout
- L04Flow thermistor fault
- L05Return thermistor fault
- L06False flame lockout (flame on before gas valve on)
- L0CRepeated restart lockout
- L0DIgnition lockout: blocked flue/condensate