Open top boiler

[lorand]

All the info I have read say´s that to prevent óff´taste from hops you should have an open top boiler so that the steam escapes. Why do breweries use closed boilers to keep in all the hop taste/aroma if its likely to cause off taste?

[Jim]

Although brewery boilers appear enclosed, they are vented through a flue.

The problem occurs when you have no proper venting at all; then steam condenses on the boiler lid and falls back into the wort.

[lorand]

So if I cut a hole in the lid and put on a small chimney do you think it would be OK.