Actuators are mechanical apparatus that convert energy into motion. The energy comes in the form of air, electricity, or liquid. The motion created by the energy is used to trigger a reaction in another mechanism or system. Various types of actuators are available including electromechanical, linear, pneumatic, rotary, and solenoid.
Rotary actuators use electricity to block, clamp or eject energy in order to move or control motors, pumps, switches and valves. They use moving coils which allow the operator to control force, position, and speed - three qualities that are also repeatable. Rotary actuators are capable of high speeds and precise position, which make them desirable for certain applications.
Furnace Rotary Actuators
Home furnaces use rotary actuators to trigger the opening of dampers and blowers. The action is triggered when the thermostat calls for more heat and sends a signal to the actuator to open a vent. Then, the open vent in the furnace sets off the series of mechanisms needed to raise the temperature in the house.
Once the damper is opened, the pilot ignition system energizes, and the main burners ignite. After reaching the appropriate temperatures, the operation is restarted to close the damper. The actuator remains idle until the next heating cycle.
How to Buy a Replacement Rotary Actuator
Rotary actuators using pneumatic energy (a controlled burst of air) can be purchased from online replacement parts vendors as well as plumbing and heating stores. The necessary specifications to buy the correct replacement include: the operating range in PSI (pounds per square inch), the maximum air pressure (in PSI), the nominal spring range (in PSI), the net force exerted (in PSI), and the net force exerted (in PSI). Pneumatic rotary actuators cost approximately $50.
Common Brands of Rotary Actuators
- KMC Controls