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Asked by: Margene Keeler
home and garden indoor environmental qualityWhat is a 2 stage gas furnace?
In this way, is a 2 stage furnace better?
A two-stage furnace runs at 70% capacity most of the time it is heating. This gives you better efficiency. The heat cycle is longer, but more consistent. The most efficient two-stage furnaces are 95% to 97% efficient.
Hereof, how does a two stage gas furnace work?
A two-stage furnace works by using a different set of programming than a normal one-stage furnace. Simply put, when it is only moderately cold inside, then the furnace's control board opens the fuel control valve to the partially open position, and heats the house to the desired temperature before turning off.
The thermostat only kicks in the second stage if the furnace can't maintain 6 to 8 degrees per hour. A two-stage thermostat may need more wires than your current programmable thermostat. If you plan to keep your home at a constant temperature, you don't need a two-stage thermostat.