P-trap

[aixha1969]

Can somebody please define this terms regarding condensation; draw-thru unit, and blow-thru unit,

[jtrammel]

Draw through is when drain is on the return side of blower and blow thru is when it's on the supply side

[aixha1969]

Thank you.

[jpsmith1cm]

Moved to Tech to Tech chat.

[timebuilder]

When you need a trap, it is because the air inside the unit at the condensate drain connection is slightly less than the atmospheric air pressure, and the water seal in the trap creates a barrier between the two areas of pressure, and allows the condensate water to run through the water seal in the trap so it can get out of the unit.

If the air inside the unit at the drain connection is at a slightly higher pressure than atmospheric air, then a trap isn't needed.