Hot water intermittant and has flow slowed to a narrow stream which stops after 10 to 15 minutes Cold water pressure ok. Engineer after numerous visits. cleared out filter and changed the pump, he could not solve the problem finally suggested replacing heat exchanger or new boiler this one is only 8 years old. Heating working fine.

GEF, February 2010

could be blocked heat exchanger on hot water side
clean or renew plate heat exchanger

dave the rave, February 2010