Valve Sizing Tool

Pseudomonad contamination - Part 3

If you have encountered retrograde Pseudomonad contamination of your taps the last thing that you should do is remove the outlet fitting.

The Optitherm Thermostatic Tap’s outlet fitting is very important and should be retained as it fulfils a number of critical functions:

Flow rate and flow condition are covered in my previous posts.

Water retention – the structure of the outlet fitting is such that it is specifically designed to retain water by surface tension when the tap is closed. If this structure were not present then the part of the tap immediately prior to the point of discharge will drain down on closure, every time the flow is terminated. The water will be displaced by air, which, as described in my flow condition post, may result in retrograde airborne contamination.

Our previous blog article 'self-purging is not the same as self-draining' gives more detail on why drain-down outlets should be avoided.

Next week I'll cover the inescapable need to routinely clean the fitting.