Has your heating, ventilation, and cooling system (HVAC) been diagnosed with a bad relay? Regardless of size or capacity, all HVAC systems have relays. They are responsible for regulating power to various parts. Relays can fail, and all it takes is a single failed relay to prevent your HVAC system from working properly.
Overview of Relays
Also known as control relays, relays are electromagnetic switches that either allow or disrupt the flow of electricity to one or more parts. You can typically find a relay in the furnace. The blower motor, for instance, will likely feature a relay. The compressor in your HVAC system’s condenser unit will likely feature a relay as well.
Blower motors and compressors require electricity. Relays regulate the power to these parts so that they function properly. When running your AC system, relays will allow electricity to flow to the blower motor and compressor. After your AC system has cooled your home, relays will disrupt the flow of electricity to these parts.
How Relays Work
Relays work automatically in response to electricity. When your HVAC system turns on – either from a manual thermostat adjustment or a change in indoor temperature – electricity will flow to the relays. Most relays use an electromagnetic method of operation.
As electricity flows to them, they’ll generate a magnetic field that completes an electrical circuit. The magnetic field will pull down part of the relay so that it completes the circuit.
When the electricity stops flowing to a relay, it will revert back to its open circuit position, meaning the part to which it’s connected will no longer receive electricity. There are different types of relays, but most of them use an electromagnetic method of operation such as this.
Signs of a Bad Relay
With a bad relay, you may experience problems with one or more parts of your HVAC system. Relays are commonly used in conjunction with the blower motor and the compressor. They ensure that electricity only travels to the blower motor and the compressor when needed.
A bad blower motor relay may result in your HVAC system’s fan not turning on. A bad compressor relay, on the other hand, may result in your AC system not turning on. You may still hear the fan turn on in the latter scenario, but you’ll likely feel room-temperature air rather than cool air coming out the vents.
If you are experiencing a problem with your air conditioning or heating call us at 512-336-1431 to schedule an appointment. We’ll be glad to come out and take a look at the issue.
1431-183 A/C & Heating proudly serves Round Rock, Georgetown, Cedar Park, Pflugerville, Leander, Liberty Hill, and North Austin.
