What about blades?
Is a fan with 5 blades more efficient than a fan with 4 blades?
The number of blades on a fan has nothing to do with efficiency, making it a matter of personal taste, rather than a purely practical consideration. The performance of a ceiling fan is determined by only 4 factors:
1. Motor speed (revs per minute).
2. Blade design & pitch (angle the blade is set at).
3. Distance between fan blades and ceiling.
4. Distance between blade ends and walls.
Motor Speed
The maximum speed of most fans is between 190rpm to 270rpm. Motor speed, along with blade pitch are critical factors in performance.
Blade design & pitch
The most efficient design is the curved aluminium blade because of its aerodynamic design and lightweight construction. The Vortex and Comet models have metal blades set at a 22 degree pitch and a maximum motor speed of 270rpm. This combination makes for a very high performance fan. Unfortunately, high performance can create air noise and this model of fan should only be used in situations where high airflows are required.
Other models in the Comfortair range which have wooden blades set at between 11 and 14 degree pitch are very quiet.
Typically, low cost fans have a blade pitch of around 7 degree. This allows the manufacturers of these fans to use a smaller motor to obtain a similar rpm to the better quality fans. However the effect of this is that while the low cost fan certainly spins around quite quickly, it moves a limited amount of air and is relatively inefficient.
Distance between fan blades and ceiling
The minimum distance between fan blade and ceiling, without affecting efficiency, is 30cm. Hugger fans and Dual mount fans installed without the downrod can have the blades as close as 16cm from the ceiling. This will reduce the airflow efficiency of the fan.Unfortunately in a low ceiling situation you have to reach a compromise between safety and performance.
Distance between blade ends and walls
There should be at least 1 metre clearance between the blade ends and any walls. If the blade ends are closer than 1 metre this will affect the efficiency of the fan and may cause the fan to vibrate. |
How do I control my fan’s speed?
There are two basic ways to control a ceiling fan’s speed.
3-speed pull chain switch
This chain is located on the switch housing on the base of the fan motor. Speeds are changed by successive pulls on this chain cycling through high, medium, low and off. This is standard on all Montana, Troppo and Hugger Series fans.
3-speed wall control switch
This is a high, medium, low capacitor type control specially designed for ceiling fans. This control is also known as a “quiet” control because it will not cause any electrical motor noise (humming). This humming will occur when dimmer switches or controls not recommended by fan suppliers are used.
All 3-speed wall controls from Comfortair incorporate a light switch which can be used either as an ON/OFF switch for the fan or to control lights fitted to the fan. Wall controls are available as an optonal accessory for fans with a 3-speed pull chain switch. When installing a wall switch on a pull chain control fan the pull chain switch must be in the high speed position for the wall control to operate correctly.
Can I control my fan by remote?
Comfortair have two remote control units that can be supplied as an accessory on all models except the Hugger Series. The receiver fits inside the ceiling canopy. This control gives you fan/light control from a remote location. It will change the speed and turn ON/OFF the light. It will NOT reverse the rotation of the fan.
The remote control unit also allows for independent control of the fan and light where extra wiring cannot be installed. The light dimmer on the deluxe control will NOT work with compact fluorescent lamps. Comfortair remote units are suitable for Comfortair ceiling fans. The use of other remotes may damage the fan & void the warranty.
What about light attachments?
Ceiling fans are often installed in locations that require lighting and in many cases they are replacing an existing light fixture. There are a variety of styles, sizes and finishes to suit any decor. Some fans are sold as unipacks, a fan and light kit, all in one box.
I’m installing a fan/light combo in place of an existing light fitting - do I need extra wiring?
Fan & light to be pull chain controlled
No extra wiring required
Fan & light to be wall controlled
An extra switch wire is required
Fan & light to be on remote control
No extra wiring required
Ceiling fans are required to be earthed. Some older homes may not have an earth wire on the lighting circuit. This can normally be installed by your electrician.
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