iv had mixer taps fitted to bath iv got pressure when shower is on but as soon as we put on the hot water pressure drops it goes down to trickle

colin daly, August 2008

Is this a thermastatic mixer as oposed to a manual control.
If it is then it could be a problem with unequal water pressures on your supply. If you have mains water pressure cold and hot from a gravity feed tank system not all mixers will work. The mixer will treat this as a fault and shut down to prevent scolding risk etc. Check the type of mixer you have against type of water feed. You may need to make alterations to your feed to equalise pressure

Robin S, September 2008