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