Aircon Technician Installing Capacitor Singapore

Aircon Capacitor Problem

Aircon Capacitor Problem & Replacement Cost Guide

Updated - Tue, 16 Jul 2024

What is an aircon capacitor?

An aircon capacitor is a type of electrical device that stores and releases electrical energy, providing the necessary power for certain components of the air conditioner to function properly.

In an air conditioning system, there are typically two types of capacitors:

1. Start Capacitor: This capacitor is used only during the startup phase of the air conditioner's compressor. When the air conditioner is turned on, the compressor needs an extra boost of power to get it running. The start capacitor stores a high electrical charge and releases it to give the compressor the initial push it needs.

2. Run Capacitor: Once the air conditioner's compressor is running, the run capacitor takes over. It provides a steady and continuous electrical charge to keep the compressor and the outdoor fan motor running efficiently.

Capacitors are necessary because they can store electrical energy and then discharge it very quickly, allowing the compressor and the fan motor to receive the necessary jolt of electricity to start and maintain their operations. Without a working capacitor, the compressor might struggle to start, or the fan motor may not run as efficiently, leading to performance issues and potential damage to the air conditioning system.

Where are the aircon capacitors located?

The location of the aircon capacitor depends on the type and design of the air conditioning system. In most split-type air conditioners, which are the most common type for residential applications, the capacitors are typically located in the outdoor condenser unit. The outdoor condenser unit houses the compressor, the condenser coil, and the fan motor, and it is responsible for expelling heat from the indoor space to the outside.

When you look at the outdoor condenser unit, you may find one or two capacitors attached to the side or top of the unit. These capacitors are often enclosed in metal or plastic cases. As mentioned earlier, there are two types of capacitors, the start capacitor, and the run capacitor. The start capacitor, if present, is usually larger and is responsible for assisting the compressor during the startup phase, while the run capacitor helps keep the compressor and fan motor running.

Indicators of a faulty Aircon capacitor?

When an aircon capacitor is faulty or malfunctions, it can lead to various problems with the air conditioning system. Here are some common issues that can arise when the capacitor is not working correctly:

1. Difficulty Starting

The start capacitor is responsible for providing an extra electrical jolt to help the compressor start up. If the start capacitor is faulty, the compressor may have trouble starting, and you might hear a humming sound as it struggles to kick on. In severe cases, the compressor might not start at all.

2. Intermittent Operation

A faulty capacitor can cause the compressor and fan motor to work intermittently. The air conditioner may turn on and off unexpectedly, making it difficult to maintain a consistent and comfortable indoor temperature.

3. Weak or No Cool Air

If the run capacitor is malfunctioning, the compressor and fan motor may not receive the proper electrical charge to run efficiently. This can result in weak or no cool air blowing from the air conditioning system.

4. Overheating

A malfunctioning capacitor can cause the compressor and other components to overheat due to insufficient electrical support, potentially leading to system shutdown or damage.

5. High Energy Consumption

When capacitors are faulty, the air conditioner may draw more electrical power than necessary, leading to increased energy consumption and higher utility bills.

6. Tripped Circuit Breakers

Faulty capacitors can sometimes cause the circuit breakers to trip repeatedly due to electrical imbalances or excessive current draw.

7. Reduced Lifespan

Operating the air conditioner with a faulty capacitor can put extra strain on other components, potentially shortening the overall lifespan of the entire system.

If you notice any of these signs or suspect an issue with the aircon capacitor, it's crucial to have a professional HVAC technician inspect and diagnose the problem. They can properly assess the capacitor's condition, replace it if needed, and ensure that the air conditioning system functions safely and efficiently. Trying to repair or replace a capacitor yourself can be dangerous and may cause further damage to the system if not done correctly.

Aircon Capacitor Replacement Cost

The cost of replacing an aircon capacitor can vary depending on several factors, including the type of capacitor needed (start capacitor or run capacitor), the capacity (measured in microfarads or UF), the brand and quality of the capacitor, and the labor charges of the aircon technician. In general, the cost of a capacitor replacement typically ranges from S$100 to S$350 USD.

As a rough estimate, you can expect to pay around $50 to $200 for the capacitor itself and an additional $50 to $150 for the technician's service. Keep in mind that these prices can vary based on your location, local market rates, and any additional repair or maintenance work required.