Understanding the SCALA1 pressure boosters performance mode selector

Using the SCALA1 performance mode selector 

The Grundfos SCALA1 is an all-in-one pressure booster. In this module, we will look more closely at the performance mode selector, which you use to adjust the pump’s suction performance.  

While SCALA1 is a fully integrated shelf product, there are still ways to tweak it to make it perfect for certain applications. 

One way to do this is by means of the performance mode selector which you will find behind the pump’s cover.

First, there’s the default position: self-priming. When set to this position, the priming valve is fully opened, giving you the best possible performance. This is particularly useful if you are using SCALA1 to lift water from wells, for instance.

Next, there’s the air-handling mode. If the water on the inlet side of in an installation is filled with air, it becomes increasingly difficult to lift the water. That is where the air-handling mode comes in handy as it opens an additional, air-handling channel. 

This helps to remove the damaging air bubbles which otherwise could affect the performance of other pumps. On the other hand, closing the valve slightly results in a small loss of performance.

Finally, there’s the positive inlet mode. In this mode, self-priming is essentially disabled as you completely close the valve and the pump is no longer able to lift water. 

This is mainly intended for situations in which there is a positive inlet connection – for instance if you are connected to a roof tank or city mains. Just remember to abide by your local laws and regulations.

One significant benefit of positive inlet mode is that it removes this sound:

This is the sound of the valve opening and closing. By operating in positive inlet mode, the homeowner has the possibility of removing this sound if they find it too disturbing.

That covers our basic introduction to performance mode selection for SCALA1.