Disclosed is a method of environmental control, comprising: passing a first air stream and a second air stream through a valve; wherein the valve directs the first air stream through a first adsorption bed and directs the second air stream through a second adsorption bed; wherein the first adsorption bed produces a dehumidified air stream, and wherein the second adsorption bed is purged of moisture by the second air stream, thus producing a purge stream; and using the valve to redirect the first air stream and the second air stream when the first adsorption bed reaches a moisture saturation point or a timed interval, wherein the first air stream passes through the second adsorption bed and the second air stream passes through the first adsorption bed.

A heat exchanger assembly includes a main heat exchanger that receives a main hot air; a secondary heat exchanger operatively adjacent to the main heat exchanger; wherein the secondary heat exchanger receives a secondary hot air; wherein the main hot air and the secondary hot air are from two different, direct air sources; wherein a hot air channel of only one of the main and the secondary heat exchangers includes a catalytic coating; and a temperature control that controls the temperature of only one of the main hot air and the secondary hot air into the hot air channel.

A heat exchanger assembly includes a main heat exchanger that receives a main hot air; a secondary heat exchanger operatively adjacent to the main heat exchanger; wherein the secondary heat exchanger receives a secondary hot air; wherein the main hot air and the secondary hot air are from two different, direct air sources; wherein a hot air channel of only one of the main and the secondary heat exchangers includes a catalytic coating; and a temperature control that controls the temperature of only one of the main hot air and the secondary hot air into the hot air channel.