Taps - Minimum Operating Pressure All aspects of plumbing questions and answers, help, tips and information

[Xander]

We are in the midst of a new build using ground sourcing heating and solar to supply hot water. The hot water tank is located in the basement. We have identified:

- a bath tap (bathroom is on the first floor) which produces a flow rate of 25ltrs per minute at 3 bar balanced pressure, and
- a kitchen mixer tap which has a minimum operating pressure of 1.5 bar.

I am struggling to get a straight answer as to can we get these taps to work in our property and if so how?

Any response much appreciated.

[plumbbob]

You will only experience problems with taps if you have them connected to a low pressure gravity fed system.

Over recent years it has become increasingly common for taps to be supplied that will only work satisfactorily if fed at a pressure greater than 1 to 2 bar. This change has been generally encouraged by the installation of new style combi boilers that are designed to work at mains pressure along with cheap imports from the continent where mains systems have been prevalent for years.

If your system has header tanks and you can stop the water flow with your finger, you will need low pressure taps designed to fit systems where the pressure is expected to be less than 0.1 bar. If the tap pressure is that of your incoming water main, this should be at least 3 bar, so any tap will do.