An air circuit for use with a respiratory therapy device, comprising: a tube portion having a helical heating element disposed thereon; and an outlet connector further comprising: an outlet connector substructure including a receiver, the receiver including receiver threads (4135.1) at a tube connection region, a first end of the tube portion and the helical heating element being threaded into the receiver threads (4135.1) such that a connection portion of the tube portion extends through the receiver, and the outlet connector substructure having an orifice positioned opposite the tube connection region; an end cap attached over the orifice; a clip configured to connect the connection portion of the tube portion to the tube connection region of the outlet connector substructure by securing the clip around the connection portion of the tube portion such that the connection portion of the tube portion is substantially surrounded by the receiver and the clip; an electrical connector attached to the helical heating element at the tube connection region of the outlet connector substructure; and an outlet connector housing molded over the outlet connector substructure; and a patient interface connector attached to the tube portion at an opposite end from the outlet connector. a tube portion having a helical heating element disposed thereon; and an outlet connector further comprising: an outlet connector substructure including a receiver, the receiver including receiver threads (4135.1) at a tube connection region, a first end of the tube portion and the helical heating element being threaded into the receiver threads (4135.1) such that a connection portion of the tube portion extends through the receiver, and the outlet connector substructure having an orifice positioned opposite the tube connection region; an end cap attached over the orifice; a clip configured to connect the connection portion of the tube portion to the tube connection region of the outlet connector substructure by securing the clip around the connection portion of the tube portion such that the connection portion of the tube portion is substantially surrounded by the receiver and the clip; an electrical connector attached to the helical heating element at the tube connection region of the outlet connector substructure; and an outlet connector housing molded over the outlet connector substructure; and an outlet connector substructure including a receiver, the receiver including receiver threads (4135.1) at a tube connection region, a first end of the tube portion and the helical heating element being threaded into the receiver threads (4135.1) such that a connection portion of the tube portion extends through the receiver, and the outlet connector substructure having an orifice positioned opposite the tube connection region; an end cap attached over the orifice; a clip configured to connect the connection portion of the tube portion to the tube connection region of the outlet connector substructure by securing the clip around the connection portion of the tube portion such that the connection portion of the tube portion is substantially surrounded by the receiver and the clip; an electrical connector attached to the helical heating element at the tube connection region of the outlet connector substructure; and an outlet connector housing molded over the outlet connector substructure; and a patient interface connector attached to the tube portion at an opposite end from the outlet connector.