A heat and moisture exchanger (HME) device for respiratory therapy, the device comprising a housing defining a passageway for the flow of respiratory gas, where the housing can include a ventilator side port, a patient side port, a first pathway defined within the housing, and a second pathway defined within the housing, a medium located within the first pathway and a valve configured to selectably impede fluid flow through one of the first pathway and second pathway during use. The HME can further include a knob configured to position the valve. The housing can include a first sealing wall and a second sealing wall, where the valve is configured to abut the first sealing wall in a first valve position and to abut the second sealing wall in a second valve position.
