extreme winter operation

[US Iceman]

Unfortunatly, many coils don't have free condensate draining.

In the past no one paid any attention to this issue. I believe the coil manufacturers are now doing a better job of engineering the coils to achieve this, although .... I am surprised that we as an industry continue to do the same old thing without thinking about how hot gas defrost actually works.

Here is how to get gravity drainage. If you can drop a marble down any of the coil circuits, the marble should roll out of the circuit.