With stainless steel heat exchangers, optional commercial rack mounts and multiple venting options, the GS and GR tankless water heater models combine reliability with flexibility to meet the demands of both residential and commercial applications and accommodate a variety of installations, the company says. Both models boast a wide array of features to increase efficiency and make service and maintenance more convenient, with the GR adding an integrated recirculation pump with dedicated connection and the GS featuring a high temperature setting of 180° for commercial use. Both models also feature cascading and common venting; variable heat control, adjustable from 95° to 140°; and bottom water connections.