We want to install electric water heating in an outbuilding to supply a shower and a sink in a small bathroom. There is an ample supply of electricity.
One possibility is to install an electric shower and a small (2kW) unvented electric water heater - basically a 10lt mini immersion heater - but we think this is too many boxes in a small space and and too wasteful.
We are also looking at a Heatstore Multiflow instant water heater at about 10kW which would supply both shower and sink and which is smaller and cheaper. BUT. The Heatflow shower kit is nasty white plastic, it appears, and over £130 for what appears to be just a mixer tap with a shower attachment where turning the hot on full establishes the flow and the cold then is used to adjust the temperature.
Can we just use any shower mixer taps, thermostatic or otherwise, in this system? There may be a pressure difference between the hot and cold, so do we need something that can cope with that, such as a pressure reducing valve? Does a standard single-lever mixer tap achieve the same result? Are we being really dense?
Any help and advice much appreciated.