Alternative-fuel gas orifice having principal-fuel gas orifice temperature profile and a heating, ventilation and air conditioning system incorporating the same

A gas furnace, comprising:

• a housing;
• a solenoid valve located in said housing;
• a manifold coupled to said solenoid valve;
• at least one alternative-fuel gas orifice coupled to said manifold, said at least one alternative-fuel gas orifice having a body having a first portion, a second portion adjacent said first portion, an aperture extending therethrough, wherein said first portion comprises a beveled end and threads, and said second portion comprises a head configured for turning said body, said body including:
• a metering neck having an entry diameter D1 and a cross-sectional area such that a given flow rate of an alternative-fuel gas is established when said alternative-fuel gas is delivered to said alternative-fuel gas orifice at a given alternative-fuel delivery pressure;
• a diffuser having a cross-sectional area larger than said cross-sectional area of said metering neck and a length such that said alternative-fuel gas achieves a substantially laminar flow before exiting said diffuser through an exit aperture having diameter D2, wherein a ratio D2/D1 is greater than 1.0 and D2 is within said second portion;
• wherein a diameter of said diffuser is between 1.1 and 1.7 times a diameter of said metering neck;
• at least one corresponding heat exchanger configured for operation with a principal-fuel gas temperature profile located proximate said at least one alternative-fuel gas orifice, wherein a cross-sectional area of the diffuser causes the alternative-fuel gas to burn in the at least one heat exchanger with a resultant temperature profile that is the same as the principal-fuel gas temperature profile in the heat exchanger at a standard principal-fuel delivery pressure;
• and
• a blower located in said housing proximate said at least one heat exchanger.