Wall Mounted, Non-Condensing Boiler Water Heater Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 7.9 GPM at 40�° F Rise, 6.6 GPM at 50�° F Rise, 5.5 GPM at 60�° F Rise, 4.7 GPM at 70�° F Rise. 199k Effective BTU/h