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The most efficient direction for the operation of a Ceil Fan View All
I would like someone to explain in scientific term the proper direction of a ceil fan for the efficient cooling in the summer and the efficient warming of a room. The definition given by contractors I believe is in error. Contractors: down in the summer and up in the winter.

I believe the opposite is true from a heat transfer and thermodynamic persective.

6 years ago - 2 months left to answer. - 2 responses - Report Abuse
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Below is an excellent article which describes the reason for the fan direction as described by your contractor.

1. Down for the wind chill effect
2. Up to clear the warm air trapped at the ceiling.

There are some modifications to this basic rule.

Niel Leon

6 years ago


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Since heat rises the air near the ceiling of a room can be warmer than at the floor. If the goal were to keep the temperature of the air in the room equal then having the fan blow down when heating and up when cooling would probably work best. However, the goal is usually to make the room comfortable for the occupants. With the fan blowing down on occupants they usually feel cooler. So down in summer and up in winter is what feels best even if it not the most efficient.

6 years ago

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