What Does My Air Conditioner’s Contactor Do?
The capacitor and contactor work hand in hand to keep you air conditioner running all summer long.
AC Power Center
Along with the capacitor, the air conditioner’s contactor works all summer long to keep power flowing to your air conditioner’s most important parts.
The contactor is essentially a type of switch that receives a low voltage signal (24V) from your furnace to power on.
By creating a magnetic field, it pulls down a piece of metal that will connect both of the higher voltage sides.
This closing of the circuit allows electricity to power the air conditioner’s fan and compressor motors.
Contactors come in generally two different types: single pole and double pole.
A single pole contains one magnetic coil that will connect one circuit.
A double pole is essentially the same thing but it has two coils and connects two circuits.
How To Know If A Contactor Is Bad
One of the most classic signs a contactor has gone bad is a loud “chattering” type of noise coming from your outside condenser unit.
Without a chattering noise, the best way to diagnose a bad air conditioner capacitor is to use a multi-meter device that measures the flow of electricity.
Also, you may notice that some of the contacts on the contactor itself may have become pitted and worn down which happens naturally over time as the contactor ages.
The average lifespan of a good contactor can be anywhere from 5-10 years assuming the unit is taken care of with annual maintenance each year.
When an AC contactor goes bad, the unit will not be able to cool the home and will continue to run even when the thermostat is turned off. The contactor is like a gateway of electricity to your system. The contactor directs electricity to various parts of the system. When it starts to go bad, it will not send electricity to refrigerate the air, but it will probably still power the unit as a whole temporarily.
With the right maintenance, a good contactor will typically last between 5 – 10 years. During a maintenance service, the technician will check the contactor to make sure it is working properly. If it is starting to go bad, the technician will replace the part with little to no hassle to the homeowner.
On average, homeowners can anticipate paying between $100 – $400 to replace an AC contactor.
Do you suspect your AC contactor is going bad? Sears Heating & Cooling can help. We offer expert repair services on any problem with your unit, including contactors. Contact us now for a free estimate or to get on our schedule!