Hi Im a bit of a cheat really. Am an electrician but have said I would do a friend a favour (luv job) and fit him a shower pump as the hot water only trickles out of his shower. I have worked out that I need a positive head pump but cant work out if I need one with 2 inlets and 2 outlets. Assume this depends on if the cold water feed to the shower is mains or tank fed. Cant remember what it was but if I had to guess would think its mains fed. My question to any half decent plumber out there is if it is mains fed cold do I have to put it to tank feed? Or can I get away with just boosting the hot water. Second little question is "are salamander pumps any good? Thankingthe plumber in advance for getting me out of this jam 
