Lid on boiler

[ade1865]

Is it ok to leave the lid on the boiler to achieve a slightly more vigorous boil? I presume this will affect the amount of wort lost to evaporation?

[anomalous_result]

One of the functions of the boil is to vaporise and drive off nasty tasting compounds, a group of them's called Dimethyl Sulfides. So it's not a great idea.

[ade1865]

ok, so how about partially covering the boiler, allowing evaporation but still increasing boil slightly. i'm worried that the boil may not be vigorous enough.

[Gurgeh]

partially covering the boiler

i know a great brewer who does just that, in fact his lid is insulated to prevent any nasties condensing on it and dripping back in.

when i say 'great brewer' i'll gloss over his 'historical IPA'

so yeah - go for it

[ade1865]

Gurgeh, could I ask how he insulated the lid?