A: The dampening effect of the Model 47 snubber is provided by the close tolerance of the piston shaft within the cylindrical chamber of the snubber. The fluid must pass through the chamber, so the larger diameter piston shaft provides more dampening and the smaller diameter piston shaft provides less dampening. The Model 47 is shipped with the medium piston (Size 2) installed which is the correct choice for the majority of HVAC water applications. If more dampening is desired, or less viscous liquids are to be monitored, simply replace the Size 2 piston with the larger diameter Size 3 piston. If less dampening is desired, or a higher viscosity fluid is to be monitored, install the smaller diameter Size 02 piston.
The piston is free to ride up and down within the cylinder as it dampens out pressure pulsations. This piston action causes the cylinder to be kept free of dirt and scale in the liquid preventing clogging of the snubber.
