Ceiling fans are a great, cost effective way to create the feeling of a cooler space in summer and warmer space in winter. They can be used outdoors as well as indoors.
Ceiling fans work in two ways. In the summer, ceiling fans create a cool breeze by spinning in a forward direction (counter clockwise) pushing air down and around the room. This increases evapotranspiration on the skin, making you feel cooler.
Ceiling fans don't actually cool the air so consider turning them off to conserve energy when no one is in the room.
In the winter, most ceiling fans can be set to rotate in reverse (clockwise). This will force the warm air, that is trapped at the ceiling, down and around the room to mix with the cool air. This will warm up the air in your room in winter. For best effect in winter, keep your fan on low speed.
TIP 1: Check to make sure that the Ceiling Fan you’re buying comes with a reversible motor that allows you change between the summer and winter option.
TIP 2: You can also use the reversible modes of a Ceiling Fan to disperse the air according to your needs. Clockwise spinning will generate a breeze directly under the ceiling fan where as Counter-Clockwise spinning will disperse the breeze to the edges of the room
Efficiency
The efficiency of a ceiling fan, especially in a warm climate like Australia, can have a large influence on the electric bill. You can save a lot of money and enjoy increased performance from your ceiling fan by choosing one that is energy efficient. Efficiency in ceiling fans is measured by the amount of airflow generated per wattage of power consumed. This is measured in ‘m3/h/W’ (cubic metres per hour per watt). Below are the results of testing done by Hunter Pacific to compare the efficiency of some common Australian Ceiling Fans.
Correct size
Many people don't think there are different sized fans for varying room sizes. Choosing the correct ceiling fan size for your room is very important to get maximum comfort and energy savings. If the fan is too small for your room it will not circulate enough air and it will be ineffective in summer and winter. If the fan is too big for the room it could overpower the room making it uncomfortable. You can change the size of your ceiling fan by changing the size of the blades.
Room Dimensions | Suggested Fan Size |
---|---|
Up to 7 m2 | 29 – 36” |
7 – 13 m2 | 36 – 42” |
13 – 21 m2 | 44” |
21 – 37 m2 | 50 – 54” |
Motor
There are higher and lower powered motors. Higher powered motors will produce more airflow and they won’t overheat as easily as fans that have lower powered motors. If you choose a motor that has sealed bearings you never need to oil it and noise won’t be a problem. Another good option is a rubber flywheel, which keeps torque under control. With a rubber flywheel, the fan is stabilised and the level of noise is reduced.
Blades
A ceiling fan has two to six blades, which are usually made of wood, metal or plastic. The major differences between the blades is the angle that they are pitched at, the material they are constructed from and the shape of the blade. The blade pitch of a fan is the angle of the blades relative to the fan. It is measured in degrees. If a blade perfectly parallel to the floor (pitch 0 degrees) it won’t produce a strong airflow. Therefore the higher a blade pitch the more air the fan moves, however this needs to be considered with all of the variables together. For an optimal airflow the blade should be pitched between 12 and 22 degrees.
The standard number of blades is four. In general you can say the more blades a ceiling fan has the more air can be circulated, up to a certain point. Then more blades increase the drag of the motor and the price of the fan. But the number of the blades is not as important as most customers think. The efficiency of a ceiling fan also depends on the strength/quality of the motor, the pitch of the blade and the right blade size.
In general you can say that metal blades are more efficient than wooden ones but they are produce slightly more noise.
You should also consider the mounting location when deciding on the most appropriate blades. There are some places in your home where ceiling fans are exposed to moisture like in a kitchen or in a bathroom therefore metal corrosion or a reduced blade life could be a problem. For these areas you should choose blades that have a rust proof finish and blades that do not warp easily like plastic or stainless steel blades.
TIP 3: Consider whether noise will be an issue for you when running your ceiling fan; choose wooden blades for decreased operational noise.
TIP 4: Consider the mounting location when selecting your blade type; Plastic or stainless steel blades will perform better in moist conditions.
Outdoor Ceiling Fans
Outdoor ceiling fans are usually installed at a porch area. They are therefore exposed to extreme temperature changes and moisture for at least part of the year. That’s why the outdoor ceiling fans are made from tough materials like plastics and stainless steel. The blades can also be made of wood but then ensure that you get timber blades that are specially treated for outdoor use. If you do use timber blades outdoors you should expect to replace the blades more frequently than moulded blades or metal blades. If the fan will be hung where it can actually get wet, you will need to ensure that it is designed to handle this condition.