In order to work as they should, residential air conditioners require a number of complex components, including wires, switches, capacitors, and more. When something goes wrong, it means that one of these components is experiencing a problem, and it requires a professional to inspect and figure it out in order to safely make repairs.
One of the problems we get called about is an air conditioner that sounds like it is struggling to start up or is “hard-starting,” meaning you might hear a hum or a buzz and then a loud bang as the compressor does finally cycle on. So what’s going on here? Read on to find out!
It May Be a Bad Capacitor
What is a capacitor? It’s an electrical part in your air conditioner that works as a temporary power source for the motors by storing and sending voltage to them. Most motors, including your air conditioner’s motor, have two capacitors. One is the run capacitor that keeps your air conditioner actually running once it starts, and the other is the start capacitor which is responsible for your system starting up.
When the start capacitor is failing or has failed, you might notice symptoms like lukewarm air coming from your vents, or strange noises (like the aforementioned hard-starting). It’s worth mentioning too that a failed run capacitor will also show symptoms, such as short cycling. If you notice any of the following signs coming from your air conditioner, one or both of the capacitors is failing:
- Your air conditioner isn’t actually blowing cold air from the vents.
- Your air conditioner’s compressor is struggling to come on or stay on once it starts up.
- You hear a humming noise coming from the system.
- Your AC shuts off on its own–before it’s reached the desired temperature on your thermostat.
- The system won’t cycle on at all.
- You hear a clicking noise coming from the AC cabinet.
It bears mentioning that these are symptoms of other cooling system problems as well. You should never brush it off as something minor–if your air conditioner is ever behaving in a way it never has before, it’s worth giving the pros a call.
“Can I Replace a Capacitor On My Own?”
We don’t recommend it–our HVAC professionals have had years of training and hands-on experience handling a problem like this.
The average homeowner won’t understand all the intricacies involved with replacing a capacitor. It must be properly sized, to begin with.
But you’ll also need one that matches the correct voltage rating and microfarad. The microfarad has to match exactly in order to be effective. Wondering what a microfarad is? The measurement of a body’s capacity to store an electrical charge–and it’s something our technicians are very familiar with!
Even the smallest mistake with installing or connecting a new capacitor or any other electrical component of your air conditioner can have hazardous results, so be sure to call on us to help!