my glow worm flexicom cx condencing boiler keeps displaying f9 fault is there any way to sort this problem out myself as my heating and hot watter does'nt work.
F9 Is low water pressure.
If the pressure is low in the boiler, top it up to between 1-1.5bar
If the pressure is high enough, then the sensing switch is most likely faulty
Carefree
December 2010
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