Navien’s NPN-120E 120,000 Btu/h non-condensing tankless water heater is offered in separate natural gas and liquid propane configurations for outdoor-only operation. NPN-120E provides 4.2 gpm at 45° F temperature rise and stays in-line with the rest of the NPN series at 0.81 UEF. NaviTech technology includes a stainless steel heat exchanger and an advanced stainless steel burner with the same very low NOx level as the NPE condensing tankless water heaters.