If you look through the pages of Inndoctor you will see the importance we place on good beer line cleaning procedures in the cellar. The basic methodology is quite simple and is covered in some detail on this site.
However there is an area which we believe we have not covered and that is the question of leaving beer lines soaking in beer line cleaning fluid over night. It seems plausible to think that a good long soak will get rid of all the yeast and bacteria in one easy hit. Not so.
Equally the old chestnut of using hot water to clean beer lines is another recurring question.
The reasons for not doing either of the above mentioned are quite simple and I will explain further.
Firstly let us take a closer look at the beer line itself. The inside of a standard beer pipe has a special microscopic lining which is designed to stop the beer becoming tainted with polypropylene tastes as it passes through. This lining is quite fragile and leaving it in contact with beer line cleaner for extended periods can strip it away, allowing a plasticised taste to form in the beer. Equally hot water and beer line cleaner should not be used for the same reason. Hot water can damage beer cooler components, tap seals and pumps as well. Another reason why prolonged soaking of beer lines does not work is that after 15 to 20 minutes the beer line cleaner losses it’s effectiveness and becomes less potent. Overnight soaking can also lead to beer coolers freezing the product coils, stopping service and requiring a breakdown call.
All brewers recommend the practice of leaving beer lines soaking overnight is avoided. Once damaged, beer pipes cannot be repaired and have to be replaced, costing hundreds of pounds.
So the simple answer is, read the label on the beer line cleaning fluid container and stick to the instructions. If for some reason you feel your beer lines are badly contaminated with yeast and require a deep clean, contact your brewery technical services for their advice.