Evaporator drain line

Looked at a house that had an electrical, split system with the evaporator in the attic. The emergency drain was visible in the front gable, but I did not locate the primary drain.

There was not a primary drain on the exterior wall, and no drains tapped into the sink / basin drains.

Can the evaporator be drained into piping in the attic?
Needs a P-trap?

Thanks,

condensate traps
Scott Schultz

Here is a thread that may help.

Nope can not connect to attic vent even with P-trap unless it is a high efficiency furnace and you stated it was electric so that ends that.

Should be able to follow the drains from the A-coil even if they are buried in insulation. My guess is the primary drain is connected somewhere to a plumbing vent and is not allowed.

Thanks, you confirmed my thoughts.
Linda