Tech Sheet #SPD 201
What is a Secondary Pressure Drainer?

Tech Sheet #SPD 202
Stall: Definition, Causes, and Effects

Tech Sheet #SPD 203
Proper Check Valve Selection and SPD Operation

Tech Sheet #SPD 204
Fill Height and Available Filling Head: Definitions and Measurement

Tech Sheet #SPD 205
Secondary Pressure Drainer (SPD) Receiver / Reservoir sizing

SPD vs. Electric Centrifugal Condensate Pumps