At low flow rates water temperature okay, increasing flow rate temperature luke warm. What controls the modulation of the boiler pressure as it would seem that more heat is required? Shower is luke warm as a result as hot and cold water is mixing is higher flow rates.
Flushed out the heat ex with drain cleaner solution and now working perfectly. Thanks for help.
allan
October 2010
most likely a blocked heat exchanger as the water flows through it warms up but when it blocked water flows through faster but boiler water flows through slower and less so water doesnt heat up as fast ideally u need to fit a iron oxide collector as this blocks the boiler ie boiler buddy or magnatec
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