what boiler

[yvonneza8]

do i need to have a combi boiler if want a mixer or thermastat shower fitted

[stanleyman]

No, if you have a conventional hot water cylinder and the height of the loft tank is not enough to give a good flow you need a dual pump from the hot and cold tank supplies called a power shower. The mains water pressure through a combi water provides the power same as an unvented mains hotwater cylinder.

[yvonneza8]

thanks so much stanleyman

[KARL]

You do not necessarily need any power shower or similar - it depends on the available pressure, which in turn very much depends on the height of a vented cylinder if that is what you have. We have a mixer (single lever type) on our shower without any pump assistance at all. We do not suffer temperature surges when water is drawn elsewhere. The height from shower head to the top level in our header tank (what matters) is just over 2m. The additional pump will guarantee adequate/even flow of hot water. You might consider trying it out without the pump - if you are dissatisfied then add the pump.

[yvonneza8]

thanks karl useful info