Hello. I'm fitting a shower and bath (shower in the bath) and while things work ok(ish) I have a bit of a pressure problem. The cold is fed from the mains in a 15mm pipe and is just fine (although I had to feed it into 22mm to fit the taps & shower valve). The hot comes via a 22mm pipe and while adequate could do with some extra pressure. The shower valve (thermostat) is designed to work with a mixture of gravity and mains. Now I have plenty of space for a shower pump but I can only find pumps that feed both supplies. I don't want to pump the cold (I think it's illegal anyway), just pump the hot. Does any one know of a supplyer of a single feed pump (with built in flow switch etc) or can you advise if it's ok to use a two feed pump (about 1.5 ~ 2 bar) but leave one side unused.