Outmyway;
You can get mixer units that supposedly work with differential pressures (mains/pumped/gravity) & you can also get pumps that will boost just one supply (usually hot) to work with cold mains pressure. This type of installation is not something I usually care to get involved with as they can be problematic, tend not to meet customer expectations &, in most cases, lead to disappointment.
It rather depends on your expectations from a power shower installation; good ones that work don’t come cheap!
You can get mixer units that supposedly work with differential pressures (mains/pumped/gravity) & you can also get pumps that will boost just one supply (usually hot) to work with cold mains pressure. This type of installation is not something I usually care to get involved with as they can be problematic, tend not to meet customer expectations &, in most cases, lead to disappointment.
It rather depends on your expectations from a power shower installation; good ones that work don’t come cheap!