EcoMax Pro 18/28E Fault Code	Possible Cause
F.1	Lack of gas, a fault with the ignition or flue, or you may need to adjust the gas valve or replace a defective electrode lead.
F.4	Ignition fault.
F.5	The system has suffered a fault due to overheating.
F.6	Your flow NTC (temperature sensor) has developed a fault.
F.17	Check the polarity of your system
F.21	The pump could have failed, over run or there could be an issue with the air lock.

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