In message , Keith D
writes
Some time ago I posted a question on how to clean a combi heat exchanger.
I resolved the issue with remarkable ease using powered citric acid at 20%
solution in water at 85 c. Cleaned it in about 40 minutes.
I was so impressed that I removed and cleaned all my right angle compression
joints!!!


Why are you posting here when you should be spending your evenings
desludging the radiators ?

c'mon man, there's work to be done

.... why did you use citric acid when phosphoric acid or hydrochloric at
RT would have done the job properly ?


--
geoff