It’s a simple idea, really, but Rheem’s H2AC represents an innovative way to save energy. The newly-introduced Rooftop Unit captures heat from the refrigeration circuit and uses it to heat water used in the building. Most systems expel the hot air into the exterior. One Arkansas restaurant, highlighted in this Rheem video, saved more than 30 percent on its monthly gas expense and another $3,400 in electric energy costs in just six months. “A lot of our customers, especially in the restaurant…