do not recommend you try this
if you DHW heat exchanger definitely needs replacing why not go for a fixed price repair?
Q
August 2015
drain water from system ,shut cold water supply to boiler.
switch of electric supply to boiler .
undo four connection from heat exchanger ,refer to boiler manual for step by step ,down lord manual from ideal Company web site,
open air vents all Radiators to drain ,close all air vent when refill from filling loop
ltd
August 2015
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