The Varistream is, among other things, designed to act as the pump pressure switch and turn the pump off when the system is deadheaded. Unfortunately many different pumps are used on systems, so to take into account all options the Varistream is fitted with an adjustment to adjust the shut off pressure (the small blue pot inside the box).
On the vast majority of systems, the factory setting of this unit will suffice, however on some systems this setting may need adjustment to tune it into the relevant pump.
Adjustment is made by turning the small blue pot one increment at a time, to increase or decrease the shut off pressure. Normally a one or two increment adjustment will be enough.
This feature will be added to the Operating Instructions.
If anyone wishes to discuss this adjustment, please ring Williamson Pumps on 0845-226-3638, who will be happy to advise.