Heater with adjustable mix regulating damper for bilevel operation

An air treatment assembly for treating and controlling an air flow, comprising:

• a ducting system, into an upstream portion of which said air flow is introduced;
• a heater element mounted at an intermediate portion of said ducting system;
• a first damper mounted in said ducting system upstream of said heater element, which divides said air flow into a first air flow portion which passes through said heater element, and a second air flow portion which does not pass through said heater element;
• a second damper, mounted in said ducting system upstream of said first and second air outlets and downstream of said heater element, which is movable between:
• a first position, wherein:
• it divides said first and second air flow portions and hinders them from mixing with one another, said first air flow portion passing past one side of said second damper, and said second air flow portion passing past the other side of said second damper;
• and a second position, wherein;
• said second damper does not substantially hinder mixing of said first air flow portion with said second air flow portion;
• said first air flow portion and said second air flow portion meeting downstream of said heater element and mixing substantially completely;
• a wall member with an aperture therein, which traverses said ducting system closely downstream of said second damper, said aperture having first and second aperture portions shifted relative to one another in the direction of movement of said second damper so that, when said second damper is in said first position, said first aperture portion is aligned with said one side of said second damper so as principally to receive said first air flow portion, while said second aperture portion is aligned with said other side of said second damper so as principally to receive said second air flow portion and,
• first and second air outlets from said ducting system downstream of said wall member, said first outlet being arranged so as principally to pass an air flow from said first aperture portion, and said second outlet being arranged so as principally to pass an air flow from said second aperture portion;
• whereby;
• when said heater element is providing heat to said first air flow portion, by moving said second damper between its said first position and its said second position, primarily warmed air may be obtained from said first air outlet and primarily unwarmed air may be obtained from said second air outlet, or alternatively, when said second damper is in its said second position, air of approximately the same temperature may be obtained from both said first air outlet and said second air outlet.