The GT-910-PIE is a fully modulating, Liquid Propane fired, tankless water heater perfect for commercial applications. With gas inputs of 380,000 BTU, the GT-910-PIE can produce enough hot water for four bathrooms in warmer climates. For Indoor and Outdoor applications with the ability to link multiple units. Can be installed either outdoors, indoors, or direct vented. Capable of supplying domestic hot water systems and/or combined domestic and heating applications (local codes dictate proper compliance). Multiple units can be combined in a system of water heaters to provide for larger applications such as hotels, large restaurants and apartment complexes. An ASME version is also available. An ASME version is also available. 15-year limited Heat Exchanger Warranty, 5-year parts warranty, 1-year labor warranty for Residential applications 6-year limited Heat Exchanger Warranty, 5-year parts warranty, 1-year labor warranty for Commercial applications HRS35 Commercial Grade Copper Heat Exchanger Low NOx emissions Non-Condensing Indoor/Outdoor model NSF certified for commercial applications Easy-Link up to four units without a Multi-Unit Controller Multi-Link up to 10 units with a Multi-Unit Controller Venting with Category III stainless steel Include internal freeze protection and multiple safty features