Skip navigation

Serving The Fresno & Madera Area

70th Anniversary of Purl's Sheet Metal & Air Conditioning

Serving The Fresno & Madera Area


On Call 7 Days a Week


Purl's Sheet Metal & Air Conditioning Blog

Electrical Troubles in an Air Conditioning System

electrical-panel-repairsAir conditioners are complicated electrical devices. The combination of an intricate electrical system and the use of chemical refrigerant makes it tricky for a non-professional to be able to diagnose what’s wrong with an air conditioner, let alone understand how to fix it.

Electrical issues are the most common type of malfunction that can bring an air conditioning system to a halt and cut off cooling to a house. Below we’ve listed the electrical malfunctions our technicians often see when they come to repair a customer’s faulty air conditioner.

Failed Capacitors

Capacitors are essential, but temporary, electrical components found in most devices that rely on electrically powered motors. The capacitors store electrical voltage like a battery and then send the voltage currents to the motors. In an air conditioner, there are capacitors for the compressor motor and the fan motors. A start capacitor sends the voltage to get the motor started, while a run capacitor sends out periodic voltage to keep the motor running.

Capacitors will eventually wear out, and they’re susceptible to extreme heat. When a capacitor begins to lose its ability to hold a charge, it will make a clicking sound. When the capacitor fails, its motor will no longer run but instead make a humming sound. Trying to get the motor to run at this point may cause it to burn out. Technicians must replace the failed capacitor.

Blocked or Dirty Contactor

The contactor is responsible for shutting on and off the electrical power to the motors. It’s essentially the internal “on/off” switch for the system. A contactor will also wear down with use and need a replacement. However, the more common problem a contactor may face is when it becomes dirty or blocked. Any accumulation of debris (such as dust or dead insects) can stop the contactor from closing. If the AC won’t turn on, or won’t turn off, it may be the fault of a contactor issue.

Overheated Motors

Mechanical stress on any of the motors can cause the wiring in the motor house to fuse together, i.e. a burnt-out motor. A burnt-out motor must be replaced, although if you notice a burning odor or grinding noise from the AC cabinets, you may be able to call in technicians to fix the motor before it overheats too far.

Bad Wiring

Wires can overheat, lose insulation, come loose, or corrode. Even a small wiring issue in an air conditioner can cause the system to trip the AC’s circuit breaker and cut off power to the unit.

It requires professionals to handle your air conditioning repairs in Fresno, CA. This is especially true for the electrical issues above. Although you can go to online retailers and purchase parts like contactors and capacitors, attempting to replace these components on your own puts you at a risk of a high voltage shock if you make even one mistake. Leave this work to our team and you can relax.

Call Purl’s Sheet Metal & Air Conditioning for great air conditioning system repairs. “Quality Is the Cornerstone of Our Success” since 1952.

Comments are closed.