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Fan Control Options



This article will explain the different types of fans switches that are available on our website.

Multifunction Switches

Many ventilation fans include multiple functions.  An example would be a fan that also includes lights and a nightlight.  You may need a switch that will control all 3 of these functions.  We have some 3-function switches that will fit in a single switching box (single-gang) and others that combine a timer for the fan - and rocker switches for the lighting functions.

Manual Timers

There are two basic types of manual timers. The less expensive are spring-wound, known as "crank timers", suitable for intermittent bathroom  ventilation. Electronic timers are more decorative and expensive but allow the occupant to select a time duration with the push of a button. Electronic timers do not produce the sometimes annoying ticking sound that crank timers are known for.   If you need a timer AND switches for other functions - we have created combo switches to serve your needs.

Delay Off Timers

 

Delay off timers are often used with fan light combinations.  A delay off timer works like a normal switch when switched on - turning both the fan and light on.  When the switch is turned to the "off" position - the light will turn off but the fan will continue to run for an adjustable interval of time.

* When toggle is up, one or two loads remain on.
* When toggle is down, load "A" is off, load "B" times-off at preset time. In the center position, both loads are off.

Usually, the timer can be easily switched using a screwdriver - timing intervals - 1 min, 15 min, 30 min, 45 min, 55 min, 60 min

Speed Controls

 

Speed controls allow the user to set the desired speed (airflow) of a ventilation device. Speed can be controlled wither continuously or in steps. One of the disadvantages of speed controls is that they can cause undesirable noise when working in conjunction with the fan's AC motor. It is best to make sure a fan can operate properly with a variable speed control before ordering.

Vacancy / Occupancy (motion) Sensors:

Vacancy sensors are very popular - especially for areas where occupants are likely to forget to turn off the fan (a classic example is a kids bathroom).  Vacancy sensors require that the fan is turned on but will turn off automatically after no motion is sensed for a set length of time.

Occupancy sensors are suitable for intermittent ventilation - and turn on automatically without a manual flip of a switch. An advantage is that the ventilation system will operate without having to rely on the occupant's interaction. The ventilation system will remain "on" and continue working for a duration after the occupant has left the room.

 

Dehumidistats

Dehumidistats can be used to turn a ventilation system on/off when relative humidity reaches a certain level. These controls are more likely to be used in bathrooms to evacuate excessive moisture. Dehumidistats have a few disadvantages. One disadvantage is that seasonal changes in outdoor relative humidity necessitate seasonal readjustments to function optimally. Another disadvantage of a dehumidistat is that they are often mistaken for thermostats and set at 70 and never adjusted. Finally, it does not automatically remove odors.