the hot water gets to 40 degrees goes cold then comes back on gets to 40 again then goes cold again, was thinking the plate heat exchanger as i have changed the dhw stat?
you are right its hot water heat exchanger drain out water from system,open all rad air vent take out heat exchanger clean out with acid put it back and you have hot water,refill water close all air vent before you refill
lal
July 2011
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