Glow worm 38Cxi F14 error code

Can anybody help with the current problem I am experiencing on my glow worm 38Cxi combi boiler.
It is all working fine as when hot water or central heating is called for.
The problem seems to be only when the system is pre-heating the water in the reserve tank. It fires up the boiler and start to heat until the F14 error code appears on the display. It sounds like the water is boiling and I can hear noise in radiator pipes!

F14 is telling you that the boiler thinks the gas valve is faulty, the wiring to it or possibly the pcb has a fault, from the MI's.

F14 is the code for flow temp above 95 degs usually means blocked heat exchanger.Check the dhw heat exch. as this normally blocks first.

richarm6 said:

Can anybody help with the current problem I am experiencing on my glow worm 38Cxi combi boiler.
It is all working fine as when hot water or central heating is called for.
The problem seems to be only when the system is pre-heating the water in the reserve tank. It fires up the boiler and start to heat until the F14 error code appears on the display. It sounds like the water is boiling and I can hear noise in radiator pipes!

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A reserve tank? I am unaware of any tank in the 38CXi.

probably confused with preheat, most likely plate h//ex fault.

Have read your post propely it could be the thermister is not connected correctly or faulty and is overheating during the preheat operation. And then dissipating heat to the central heating system to cool down.If it is turn off pre heat untill thermister changed

if the NTC is faulty it will more likely give fault code indicating this..6, 7 and 10. F14 is nearly always plate h/ex. it will do it more on preheat cos theres no water running to take the heat away.....whip it out&rinse it through, probably full of black bits from your system. if it is, think about fitting a maganclean

I have had a 38CXi for the past 3 years and without doubt it has been an unmitigated disaster from the word go - faulty part after faulty part. Unfortunately the original plumber deemed to site it in my loft space over my lounge. Advice for anyone out there - NEVER be talked into this! There is only one place for the leaks to go and that's straight down into your lounge or wherever. After the guarantee expired I should have cut my losses and bought another model, but state pension being what it is that was not an option. I have had 4 major floods and 2 minor issues. Each time it is another failed part, I have spent enough money to have replaced the damn thing, but that's the wisdom of hindsight. I don't have the technical expertise to explain the varying failed components but I did ask Plumber no 4 to qualify yesterday and the latest problem is the L.H. hydraulic block (?) This was replaced a week ago with genuine Glow Worm parts, I went away over Easter and came back to yet another flooding scenario - the new part was faulty. Fortunately my new bank account covers home emergencies......this should not be, How have Glow Worm got away with such an inferior product?