I can get central heating to full level but domestic hot water gets only luke warm. Have fitted new heat exchanger to no avail,the setting controls don`t seem to have any effect, what else could be the matter ?
heater is a vaillant combi R S F very old but like a Rolls Royce inside .
You'll have to be more specific about your boiler model, there is no Vaillant combi R S F model as such.
It is old you state, so it could be one of the following:
Sine
VCW
VUW Turbomax
Carefree
March 2011
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