Is Your AC Facing Contactor Problems?

Air conditioning units can have several problems over time. While some are a matter of cleaning air ducts and filters, many of them must be addressed by an HVAC contractor. They may develop into much bigger concerns if not handled professionally.

 

One issue you can encounter is contactor problems, where bad electrical contacts cause your appliance to malfunction or stop working. While an AC repair in Marietta, GA, can fix this, learning more about them will help you assess the situation early on.


What's a Contactor and How Does It Work?

The contactor is one of the main components of air conditioning systems. This control device connects and breaks the power supply lines running through a load. It allows electricity to pass from the outlet to other parts of the equipment. It also cuts the current to stop the appliance from operating.

 

Inside the contactor is a pair of latching electrical contacts, which acts like a drawbridge that opens and closes. To let power flow freely, it has to touch; to break the supply lines, it needs to separate. When it wears down or gets stuck in one position, that's when you'll have problems, so you have to call for an air conditioning repair.


What Leads to Faulty Contactors?

Your contactor will start failing when the electrical contacts wear down. They may corrode when exposed to moisture, oxygen, and acidic substances. They can also decrease in size when they constantly rub together, causing their surfaces to wear down layer by layer.


When either of these happens, their ability to conduct electricity decreases. So, the energy that's supposed to flow through the contacts dissipates elsewhere, producing arcs. These are bright orange or bluish-white sparks of electric discharge that appear in a split-second.

 

Arcs are extremely hot. They can melt cable insulation if they occur frequently, which leads to short circuits. They can also weld your contacts together, keeping the pair shut and thus preventing you from turning your equipment off. Your technician will have to replace the whole contactor to fix the problem.


How Can You Tell If Your Contactor Is Failing?

Before you call an HVAC specialist, inspect your unit thoroughly so you can better describe the situation. Here's a checklist of what you should notice if you're looking at a malfunctioning contactor.

 

·         Charred or Melted Casing - Arcs can melt the contactor's plastic box. You may also notice a burnt smell and some charring on the casing.

 

·         Chattering and Humming Noises - When the metal coils, plunger, and contacts erode, they gradually become loose. So, as the machine vibrates, they shake and make a chattering sound.

 

·         AC Not Turning On or Off - The contacts need to be separated to turn an appliance off. So, when these metal strips are welded together, your AC continues to run until it's unplugged. Contactor problems can also prevent an AC from turning on. Its contacts might be stuck in an open position because of dust or dirt that has accumulated in the system.

 

Having a basic understanding of how AC parts work and what can wear them down is the key to taking better care of your unit. It also helps to learn a little troubleshooting. But, when a problem still exists after you try to fix it, it's time to call the experts. Get in touch with Shriver Mechanical, Inc. to repair your air conditioning unit in Marietta, GA.