Gas furnace and air conditioner having the same

A gas furnace, comprising:

• a burner configured to burn fuel;
• a heat exchanger that extends longitudinally and provides a passage for combustion gas generated by the burner;
• a blower configured to cause a flow of air passing around the heat exchanger;
• a plurality of guides through which the heat exchanger penetrates and spaced apart from each other in a longitudinal direction of the heat exchanger;
• a top plate positioned between the heat exchanger and the blower, and having a top hole through which air passes;
• a bottom plate that faces the top plate with respect to the heat exchanger;
• a mount plate positioned between the burner and the heat exchanger;
• and
• a side plate that faces the mount plate with respect to the heat exchanger, wherein the heat exchanger comprises:
• a first tube that forms an entry of the heat exchanger;
• a second tube that forms an exit of the heat exchanger and spaced apart from the first tube in a direction crossing the longitudinal direction of the heat exchanger;
• and
• a bend that connects the first tube and the second tube, wherein the plurality of guides is alternately disposed in a direction in which the first tube and the second tube are spaced apart from each other, wherein the first tube and the second tube extend in the longitudinal direction of the heat exchanger, wherein the plurality of guides comprises:
• a plurality of lower guides penetrated by the first tube and sequentially arranged along the first tube;
• and
• a plurality of upper guides penetrated by the second tube and sequentially arranged along the second tube, wherein the plurality of lower guides is disposed vertically with respect to the first tube and spaced apart from the second tube, wherein the plurality of upper guides is disposed vertically with respect to the second tube and spaced apart from the first tube, wherein the plurality of upper guides is positioned above a first reference line that extends in the longitudinal direction of the heat exchanger between the first tube and the second tube and intersects a center of the bend, wherein the plurality of lower guides is positioned below the first reference line, wherein a distance between the first reference line and a second reference line that extends in the longitudinal direction of the heat exchanger between the second tube and the top plate and positioned below the top plate is equal to a distance between the first reference line and the bottom plate, and wherein the plurality of upper guides respectively further comprises openings formed to pass through the plurality of upper guides and aligned with the second reference line.