Heil 80% AFUE R454b

80% AFUE Upflow/Horizontal Gas Furances , Single-Stage, Standard, R454b

How to calculate BTU

Home total finish square footage X 30 = Minimum BTU

ex: 1560 sqft x 30 = 46,800 Btu / 0.8 (80% efficient) = 58,500 btu = Size needed = 60K