A wall mounted heat exchanger including a plurality of panels. Individual panels may include a first end, a second end, a first sidewall, a second sidewall, a first gap disposed along the second end, and a second gap disposed along the second sidewall. A first plurality of panels may be arranged such that first ends of the first plurality of panels are co-planar with second ends of a second plurality of panels and first sidewalls of the first plurality of panels are co-planar with second sidewalls of the second plurality of panels. The first plurality of panels and the second plurality of panels, when arranged, may form a plurality of first inlets from the second gap, a plurality of first outlets from the first gap, a plurality of second inlets from the second gap, and a plurality of second outlets from the first gap.