GeoComfort Residential Series Compact Horizontal Packaged (ZS/ZT) heat pumps are small and versatile, fitting between standard 24" trussing. The small size of these heat pumps make them perfect for replacing older water-source heat pumps. These models come standard with hot water assist for 25% - 40% savings on hot water costs annually. As a lighter unit with high efficiencies, these systems are ideal for small to large homes, net zero homes and buildings, new and existing homes, storage buildings, and more.