I have an 80 and no trap between the humidifier and condensate drain. My drain is plumbed directly into the sewer and there is a trap there, but it has occoured to me that since there is an opening at the humidifier where air can be sucked in, and a place for it to go into the air handler through the drip tray, that I need another trap.
Originally posted by trane
Great, now all 90,s are going to be double trapped. It won't hurt but it also won't help. All you are doing is adding a likely place for the drain to cause future problems.