49 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 47-116-17 | Ecogenus 24 MFFI | 2000–2002 |
Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.
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Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent internal damage.
After three attempts at ignition, no increase in ∆T was detected
Your boiler has tried multiple times to start but failed to produce a flame, so it has safely shut itself down to prevent a gas buildup.
Too many failures to flame in one period during operation
The flame was detected after the gas valve had closed
The flame was detected before the gas valve opened
does not close
does not open
Problem with the fan
Problem with the electronic monitoring
Too many attempts to ignite on starting up
After three attempts at ignition, no increase in DT was detected
The heating flow temperature exceeds 100°C during operation
Too many failures to flame in one period during operation
The flame was detected after the gas valve had closed
The flame was detected before the gas valve opened
The flow switch does not close
The flow switch does not open
Problem with the fan
Problem with the electronic monitoring
Flow temperature over 100°C while boiler is not in operation (stand-by)
Your boiler is failing to ignite the flame needed to heat your water and radiators, despite a few automatic attempts to start.
Your boiler has detected that the water inside the system is getting too cold and has switched on its internal pump to keep the water moving and prevent freezing.
Your boiler has detected that the water level inside the heating system is too low to operate safely.
Your boiler has detected that a flame is present even though it has commanded the gas supply to shut off, which indicates a serious safety monitoring fault.
Error in the electrical connection (live and neutral crossed)
Your boiler is failing to detect the airflow needed for safe operation, so it has shut down to prevent any risk.
Your boiler has detected that the internal exhaust fan is not spinning fast enough to remove combustion gases safely, so it has shut down to prevent a hazard.
3-way spring kit
Your boiler is struggling to accurately measure the temperature of the water being stored or prepared, which is preventing it from heating your home or taps correctly.
Your boiler has lost the ability to accurately measure the temperature of the water being stored for your taps, causing it to stop heating water to prevent a potential malfunction.
Heating flow temperature probe in open circuit
Heating return temperature probe in open circuit
Heating flow temperature probe
Heating return temperature probe in short circuit
Problem within the electronic system
Flow temperature over 100°C while boiler is not in operation (stand-by)
Domestic hot water temperature probe in open circuit
Domestic hot water temperature probe in short circuit
Under floor heating temperature probe in open circuit
Flame detected with gas valve closed
Error in the electrical connection (live and neutral crossed)
Problem with the 50Hz power supply
Flame detection electrode short-circuited
Heating flow temperature probe in open circuit
Heating return temperature probe in open circuit
Heating flow temperature probe short-circuited
Heating return temperature probe in short circuit
Problem within the electronic system
BoilerFaultCodes