Ive been experimenting with this over the last few weeks and it seems to work well, if its wrapped up you may just lose 10c over 8 hours... I have had to do it due to work commitments and so far I've been brewing a few stouts and all is good! Just make sure you get your sparge water in the 80's in order to get the whole thing up to temperature again.. Learnt that off graysalchemy :