How soon to add yeast

[Cwrw666]

I have played it "fast and loose" on initial temps in the past, but only with US05 or Belgian sort of yeasts (Belle Saison or MJ's M31, that sort of thing) and pretty much noticed no difference in end result. It is once it starts the actual ferment at 20+ hours that you are in more difficult terrain, I feel.

Yeah, I think if there's a krausen you want the wort in the correct temperature range. Before or after it'll be fine as long as it's not so hot as to kill the yeast.

 

[Slid]

Its been between 21 and 22 (22.3°C max peak) since it started fermenting. I had not considered it generating its own heat (I am new to this)

My last brew (my very first ever) was between 17 and 20 throughout and it turned out just wonderful. The instructions say keep between 19 & 21 - will a degree too high make much diff ?

No, it will not. If you were a commercial brewer, consistency is almost everything. Since it is your beer, you won't care, as it will be no worse, if perhaps a very (very) small bit different.

 

[GerritT]

What happens if it is too warm, does the yeast die ?
And what happens mid brew if there is a heat wave and the temp goes back up to 25 (unlikely I know) but would that kill the brew

It will become beer, after 2 weeks you will bottle it, another 2 weeks further you cannot control yourself anymore and you will crack one open, and you will like it. That's how it goes. And you will want to brew again that very same day.