Question:I am curious to know the function of a vent on an ATU. Homeowners hate to see them, hiding them costs time and money, and they can be a source of odors. I install Clearstream units, and they don’t have a vent. They seem to work just fine. If the ATU can vent through the house plumbing stack (which it should unless there is a serious dip in a pipe that creates a P trap) and the air pump is not drawing more amps than it should, why do most manufacturers install a vent?Answers:Not all ATUs are created equal. Some
