OP
BES
I know you can get heaters for whirlpool baths but didn't think they were no more than 1.5 kw and the pumps about 750w ( about 1 hp) now if your talking hottubs obvouisly thats a different beast altogether.Actually this is a very good question. Reason I have wired a couple that had 2 16 amp supplys, one for the blowers and one for the heater. To be fair though they were considered large, the average whirlpool is 4 kw, also agree with hawkmoon and trev about ignoring the plumber and getting proper advice.Is the flex just suppling the pump for the blowers I take it there isn't a heater fitted as well.