The Raypak 106A and 156A heaters are the perfect choice for above ground pools and spas. Raypak is the only manufacturer of these size heaters to use all the engineering and components utilized in our bigger gas heaters. These units are fully serviceable and built for years of operation. These small heaters are built to the same exacting standards as the rest of our products. Extend your swim season, open your pool earlier and close it later.