Two-stage furnaces give you the option of lower, more energy-efficient heating when full burner output isn’t required. Here in the Arizona climate, that’s most of the time. However, a single-stage furnace doesn’t give you that option. The one-stage burner produces full-blast, 100 percent output all the time it’s lit. That’s an energy-waster and not the best choice for comfort, either. One-stage heating produces wide temperature swings as the furnace cycles on and off. Room temperatures may fluctuate as much as 10 degrees above and below the thermostat setting. Here’s how two-stage furnaces get the job done better and more efficiently.
The furnace always cycles “on” at the lower burner setting, about 65 percent of maximum BTU output. As long as the heating load requirements of the home are met, the furnace remains in low-output mode. If unusually cold weather demands more heat faster, the burner automatically advances to 100 percent output, but only for as long as required to meet the thermostat target temperature. Then, it drops back to the lower, energy-saving output to maintain the temperature. Here’s why two stages are better than one:
Energy consumption declines proportionally as the furnace runs at 65 percent output versus 100 percent. In our climate, this results in lower operating costs at least 80 percent of the time.
Heating is more consistent. The acute temperature fluctuations of single-stage mode are evened out. A two-stage furnace can typically produce temperature variations of just two degrees above or below the thermostat setting.
Two-stage operation is quieter. Much of the sound of furnace operation is burner noise transmitted through the ductwork. At lower output, the burner produces substantially fewer decibels.
Lower output means less wear and tear inside the furnace, longer service life and fewer maintenance issues. Critical furnace components such as the heat exchanger receive less stress when temperature variations are reduced by the lower output mode.
There you have it! You still want more information call today to speak with your Heating & Cooling Specialists!