I don't think Ireland will offer any better chances.
never had any frozen pumps/tanks etc.answer is a heater in the van overnight.never had a drought order in north west england.my fuel consumption is minimal due to nearly all work within a 8 mile area.most very compact.and just to pee all them off who live in hard water areas.my tap tds is 31 at the moment!so my resin lasts 4-5 months before needing changing!! i know...i know!!im very lucky!!!
tds 31,why dont you use an r/o instead of resin?