Roger O wrote a full procedure for winterising your equipment.
Cheers BDCS it is most proberbly way down in this section now

DS
You are going to have to let your machine de-frost naturally, don't be tempted to pour boiling hot water over the pump as this could do damage, IE split seals etc. Run an anit-freeze soultion through it every time you finish using at this time of the year and you shouldn't have any problems.