Why does the indoor blower motor in a furnace continue to operate after the furnace shuts down?

Why does the indoor blower motor continue to operate in a furnace after the furnace shuts down? Final answer: The indoor blower motor in a furnace usually continues to operate after the furnace shuts down to distribute remaining heat, improving energy efficiency.

Explanation:

When a furnace completes its heating cycle and shuts down, various components like the gas valve, HSI (Hot Surface Igniter), and burners are switched off. However, the indoor blower motor might continue to operate. This is typically designed to ensure the remaining heated air in the furnace is distributed throughout your home, and not wasted. The process is known as 'Fan Off Delay' and is a common feature in modern heating systems to improve energy efficiency.

In some cases, if the blower motor continues to operate for a long time after the heating cycle has completed, it might indicate a problem with the furnace settings or a faulty component. It is advisable to consult a professional HVAC contractor if the blower motor operation seems excessively long.

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