RIS Fermentation issues

[Orval62]

Yesterday I brewed a BIAB RIS from the Greg Hughes brew book and hit the starting gravity of 1080. Having transferred it into the FV I added a Wyeast London ale yeast smack pack. It's been 24 hrs and still no activity from the airlock, any suggestions?
As I'm concerned I have placed the FV on a heating tray to see if that will kick start it into action. Never used a smack pack before I tend to rehydrate dry yeast, should I put another yeast into the FV or be patient any advice appreciated. 👍

 

[strange-steve]

It sounds like you didn't make a starter, in which case you've under pitched by quite a lot. It will ferment but you might find it'll have a bigger lag time than usual. You may also get some funky fermentation flavours, but not necessarily.

 

[IainM]

Yeah big beers need a large healthy starting population to ferment cleanly to completion, and liquid yeasts can have poor viability, especially if it's been more than a couple of months since manufacture. I'd be tempted to chuck in a couple of packs of s04.

 

[Orval62]

Followed the instructions on the Wyeast smack pack and it appeared to have activated with the pack bulging prior to putting it into the FV, but having not used them before I have limited confidence in it. Looks like off to the LHBS on Tuesday.

 

[DoctorMick]

I'm pretty sure the packs say to use a starter for anything over 1.060. I'd definitely add more yeast if you can.