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