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DHW Run's hot and then goes cold?
Ferroli Boiler Optimax HE 31C?
what part do ineed?
Can't get hot water but central heating is working fine, any ideas??
High pressure on my Optima Ferolli 901 central heating?
c/h hotwater?
shower in bathroom keeps going hot then cold then hot etc?
DHW running hot then cold?
how can i fix this ?
falling presher?
2 amp fuse blown?
ferolli modena 102?