Fault Code	Possible Cause
F.00, .04, .05, .10, .14, .15	All of these are NTC faults, and are best resolved by first changing all NTCs to make diagnosis earlier.
F.21	The pilot flame has failed.
F.22	There is insufficient water in your system
F.11	A blockage in the appliance is preventing the system from flowing as it should
F.12	A blockage in the appliance is getting the system’s pressure
F.13	The appliance is blocked because of a water deficiency

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