There are several components of systems that drain or pump condensate. Two of the more common, effective types of devices to accomplish this task are electric condensate drains/pumps and secondary pressure drainers. An electric condensate drain or pump is relatively self-explanatory, using electrically powered components to drain or pump condensate when needed. A secondary pressure drainer is a vessel which collects and discharges liquid by alternately pressurizing and depressurizing through a given valve arrangement, utilizing a secondary, compatible vapor or gas pressure as the motive force rather than an electrically powered component. The purpose of an SPD is to transfer a liquid from point A to point B using a vapor such as steam, air, or a compatible inert gas under positive pressure to push the liquid out of the vessel and into the discharge line. SPDs are used most commonly to collect and pump steam condensate.
Type 1
Type 2
