I moved a belgian dark into secondary about 4 days ago. The yeast cake has been sitting in the primary carboy ever since. I placed the cap with air lock back on the carboy after I drained it. Is there a time consideration for letting it sit before I wash it ?
Nope. I wash my yeast right away. Never had a problem.
Ok, well maybe not right away, but after I’m done bottling or racking to secondary.
Are you asking if you can wait a week or two before rinsing the yeast? If so; It is better to do it as soon as possible. Without your beer sitting on top of the yeast cake the protective layer of alcohol allows for greater risk of contamination.