Relay Used in HVAC-R Mechanical Systems

HVAC-R stands for heating, ventilation, air conditioning and refrigeration mechanical system. In HVAC equipment, relays are often used as switches for power circuits such as compressors, fan motors, water pumps, and four-way valves. When in use, one end of the electronic relay control coil is connected to the power supply, and the other end is connected to the output end of the control component. Through the output control signal of the control component, the two ends of the relay control coil generate a potential difference and form a current loop to generate electromagnetic force. Under the action of the electromagnetic force and the inherent elastic force of the relay reed, the contacts of the relay are pulled in or released, so as to connect or disconnect the circuit of the electrical load power supply to control the operation or stop of the related equipment.

HVAC relays open or close circuits to turn equipment on and off. Also known as control relays, these magnetically operated switches are commonly used in fan motor operations such as air conditioning, heating, and ventilation systems.