shower pump not switching off

[armytouch]

Hi hope you can help, i have a mixer shower head but very low pressure from hot water so have installed a shower pump under the bath connected to the hot and cold water,the hot surply is on a 22mm pipe and the cold on a 15mm pipe. The 22mm reduced to 15mm through pump then back to 22mm after. I am using a new team pump however if doesnt seem to switch off when taps off, it as cables from each side into control panel i assume these are the sensors to cut off. The motor seems to just keep going, one of the pipes was twisted so not sure if this would affect it. Can anyone explain what could be causing the problem of the motor not switching off,thanks

[plumbbob]

If the cold feed to the bath is 15mm, it suggests it is at high pressure, and shower booster pumps cannot be connected into a mains supply for several reasons. One, but probably not the most important reason, is that normal shower pumps are not designed to withstand the pressure of mains water. The pump bearing water seal and indeed the housing if made of plastic, will very likely fail in time. This also may be the reason the pump won't shut off.

Power mixer showers must have their own dedicated hot supply direct from the hot water cylinder and separate cold water supply from the header tank. Please read the installation manual and ensure the mixer shower has been installed correctly.