Furnaces and boilers
Furnaces and boilers -
(1) Furnaces.
(i) The Annual Fuel Utilization Efficiency (AFUE) of residential furnaces shall not be less than the following for non-weatherized gas furnaces manufactured before November 19, 2015, non-weatherized oil furnaces manufactured before May 1, 2013, and weatherized furnaces manufactured before January 1, 2015:
(1) Furnaces.
(i) The Annual Fuel Utilization Efficiency (AFUE) of residential furnaces shall not be less than the following for non-weatherized gas furnaces manufactured before November 19, 2015, non-weatherized oil furnaces manufactured before May 1, 2013, and weatherized furnaces manufactured before January 1, 2015: