Short #48 – Drains (Podcast)

In this short podcast episode, we talk about condensate drains. We get into the basics of cleaning, pitch, drain pans, and more.

Cleaning drains sounds like an easy task, but it can be a bit time-consuming and difficult to get right. Instead of just “blowing out the drain,” you must check the entire drain and be aware of buildup in traps and other hard deposits that form inside the piping. Sometimes, you may need to use cleaners to dissolve the sludge and grime. Cleaning is about understanding the drain anatomy and checking it thoroughly to identify and attack the source of the buildup. You also need to clean the drain pan.

Drain pitch is also important for proper drain operation. The horizontal runouts need a slight downward pitch to move the pipe contents. We recommend using 1/4″ per foot of fall on horizontal runouts. Insulation is also important on horizontal runouts in areas like attics and other unconditioned spaces.

Secondary drain pans should have about 3 inches of overlap in all directions, especially over the supply. Improper drain pan setup can cause messes later, and we don't want condensate dripping all over the place. Make sure you install your units in the proper configuration. Be willing to tweak the design to make sure the drain pan is sturdy and collects condensate well. As you would ensure that your unit is level, you need to make sure the secondary drain pan is level and supported properly.

You also need to think about float switches. If you have multiple float switches, you need to wire these in series. These components also require thorough testing; each one should be able to break the circuit.

We also discuss:

  • Strapping the drains
  • Venting
  • Double-trapping

Learn more about Refrigeration Technologies HERE.

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