What is the Air Conditioner Capacitor?

An air conditioner capacitor is an electronic component used for starting and running air conditioning motors, storing and releasing electrical energy for improved efficiency and stability of an AC system. Think of AC capacitors like shiny cylindrical batteries – their job is keeping your cooling motors going during times when cooling is necessary!

The Principle of Air Conditioner Capacitor

Your air conditioning’s outdoor unit contains one of the most essential parts of its HVAC system: an air conditioner capacitor. Capacitors store electric charge using an electric field between two metal plates and when more energy is required in a circuit they release that stored charge, providing extra power to the motor.

AC capacitors provide the initial power required by the air conditioner motor to operate successfully. It stores electricity and sends it to the system’s motors in powerful bursts, causing your equipment to accelerate as it initiates a cooling cycle. Once the AC is up and running, the capacitor reduces its energy output but still provides a steady current until the cycle is over.

AC capacitors are measured in voltage and microfarads. Voltage measures how much current flows through a capacitor; as voltage increases, more current flows through faster. Microfarads measure how much current can be stored; most capacitors range in capacity between 5 MFD (microfarad) to 80 MFD.

Capacitors may appear similar to batteries, but they’re actually different – they connect directly to the wiring inside an air conditioning system and cannot simply be swapped out by opening its door and installing a new capacitor inside. When replacing AC capacitors yourself as high-voltage devices can still cause severe injuries even with power turned off (we will discuss further about this later).

Types of Air Conditioner Capacitors

Air conditioner capacitors come in two varieties; starting and running capacitors. The former provides instantaneous high voltage to help start quickly while the latter supplies steady AC current to help ensure smooth running operations. The two functions differ; with starting capacitors providing immediate high voltage that helps start quickly while running, capacitors provide steady AC voltage to enable stable operation of compressor and fan units while running.

How to Check the Air Conditioner Capacitor?

There are many ways to check air conditioner capacitors. A multimeter, AC power supply or special instrument may be used to measure their resistance, charge and discharge status or actual capacity. If an air conditioner capacitor is found swollen, leaking, short-circuited or open-circuited it must be immediately replaced with another capacitor of its model type.

Why Are Air Conditioner Capacitors One of the Most Commonly Replaced Ac Capacitors?

AC capacitors are one of the most frequently replaced parts in an air conditioner, since if they become defunct they may prevent your entire HVAC system from functioning as expected and force you to run your AC harder, leading to either wear and tear or increasing energy bills.

How to Choose an Air Conditioner Attendant?

Air conditioning capacitors should be selected according to their capacity and pressure specifications based on the model and power rating of an air conditioner, so as to optimize performance and life. Failing to do so could significantly decrease performance or lead to abnormal cooling; damaged capacitors needing replacement may even prevent start up altogether or lead to inefficient cooling – therefore regular inspection and replacement must occur.

How to Test an Air Conditioner Capacitor with a Multimeter?

An air conditioner capacitor is a device which stores and releases electrical energy for starting and running an AC motor, with improper functioning causing hard starting, humming noises or no cooling at all. To test an air conditioner capacitor with a multimeter you should follow five steps.

Step1:Switch off power to the AC unit, disconnect its wires from capacitor terminals and avoid touching them as they may still contain electrical charges.

Step2:To safely discharge a capacitor, short its terminals with an insulated screwdriver or jumper wire using an insulated screwdriver – this will avoid electric shock or damage to your multimeter.

Step3:Review the capacitance value on the exterior of a capacitor and read its written specifications; this should be expressed in either microfarads (uF) or picofarads (pF). For instance, one capacitor might bear the label “40/5 uF 370 VAC”, meaning it has two capacitance values – 40uF and 5uF – that together provide up to 370V of alternating current voltage handling capacity.

Step4:Set your multimeter to its capacitance setting. If there isn’t one available, an ohmmeter setting could work instead but may produce less accurate results.

Step5:Connect a multimeter to the capacitor terminals. If your capacitor contains two capacitance values, test each individually before making your decision. For instance, if it says “C/H” and “FAN”, connect one lead of your multimeter to “C/H”, one to “COM”, and so on – repeat for each set of terminals until all have been tested successfully.

Check the multimeter reading and compare it with the printed value. Ideally, it should fall within 10% of its printed value; for instance if 40uF was printed as its value then ideally reading should fall between 36 uF and 44uF; any deviation beyond this range indicates that your capacitor may be defective and should be replaced immediately.

Air Conditioner Capacitor Wire Colors

The wire colors of an air conditioner capacitor serve to indicate its position in relation to an AC system. As this may vary depending on its manufacturer and type, it is wise to check your wiring diagram first before beginning installation of any capacitor. According to one source1, an AC capacitor’s wiring color code includes:

• Brown: This wire connects to the fan motor.
• Yellow: This wire connects to the compressor.
• Common: This wire connects to the power source and is usually black in color.