Multi Stage Furnaces
Multi-stage furnaces utilize variable speed blowers as compared to single stage furnaces that cycle on and off. The multistage gas furnaces use an efficient variable-speed blower motor.
Single-Stage vs. Multistage Furnace
Typical furnaces have single-stage burners. These burners are either on or off. More sophisticated furnaces have multistage burners. Instead of being either on or off, multistage burners are able to vary their heat output to more closely match the load created by the outdoor conditions. The result is more even comfort in heating mode, because such multistage furnaces run more continuously on a lower fire setting when compared to a single-stage furnace of the same total heating capability. In addition to ensuring more even comfort, less starting and stopping is associated with multistage furnaces. The net result is that multistage furances experience less wear and tear on their components, and they provide better overall efficiency. Multistage burners are available that fire at two or more discrete levels of output, as well as models that are completely modulating. Furnaces with more stages or which completely modulate provide the most even comfort.
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