Central Air Troubleshooting - Top 10 AC Problems

Summary

In this video, Jay from Word of Advice TV shares his insights on the top 10 most common air conditioning (AC) problems based on over 240 service calls. He discusses frequent issues like bad capacitors, low refrigerant, clogged condensate drains, and faulty control boards, explaining how they affect performance and providing tips for repairs. Jay emphasizes the importance of regular maintenance, such as cleaning filters and coils, to prevent costly breakdowns. Whether you're a DIYer or need a technician, this video offers valuable advice for keeping your AC running smoothly and avoiding common pitfalls.

Takeaways

• 😀 A bad capacitor is the most common AC issue, accounting for 52 out of 242 service calls. It can cause the AC to malfunction, and sometimes it bulges or pops, leaking dielectric grease.
• 😀 Low refrigerant (Freon) is the second most common problem. An AC is a sealed system, and if refrigerant is low, it indicates a leak, often in the evaporator coil, which can be costly to repair.
• 😀 A plugged condensate drain can cause water to leak from the furnace, even if the AC is cooling properly. This is usually caused by blockages in the drain hose or fitting.
• 😀 A faulty control board can result in various issues, such as no power to the outside unit or erratic behavior like the furnace turning on when the AC is running.
• 😀 A burnt-out condenser fan motor can prevent the fan from spinning, causing the compressor to overheat and eventually trip the breaker. Replacing the motor is usually necessary.
• 😀 A bad blower motor can cause no airflow and a burning smell. If the motor hums but doesn't turn on, it’s likely the capacitor needs to be replaced, but the motor may also need replacing.
• 😀 A dirty furnace filter is a simple issue that can cause airflow restrictions, leading to frozen coils and poor cooling performance. Regular filter changes are essential for proper system function.
• 😀 A tripped AC breaker is often caused by a short somewhere in the system, like broken or corroded wires, or a malfunctioning compressor.
• 😀 There are several other common issues with 6 calls each, including low refrigerant levels, dirty condenser coils, bad contactors, leaking drain pans, and damage caused by rodents or broken wires.
• 😀 Some honorable mentions include blown fuses, faulty thermostats, vandalism, and occasional issues like a faulty transformer or switch that prevent the system from operating correctly.

Q & A

What is the most common problem encountered in air conditioning systems?

The most common problem encountered is a bad capacitor, which accounted for 52 out of 242 service calls. A failed capacitor can prevent the compressor and fan motor from starting.

How can you tell if a capacitor is faulty?

A bad capacitor may show visible signs like bulging or a popped top, although sometimes it may look normal yet still fail. The best way to check is using a multimeter or simply replacing the capacitor as it is the most common fix.

What causes an AC unit to be low on refrigerant?

Low refrigerant levels usually indicate a leak in the system. Since AC units are sealed, the refrigerant should last for the life of the unit. Leaks are often found in the coil, line set, or at the brazed joints.

What should you do if the refrigerant level is low?

If the refrigerant is low, you need to first identify and repair the leak. In some cases, the coil needs to be replaced, which is often more cost-effective than repeatedly refilling the system.

Why does an AC unit freeze over when it’s low on refrigerant?

When the refrigerant level is low, it can cause the coil inside the furnace to freeze over because the system is not circulating refrigerant properly. This leads to restricted airflow and ultimately ice buildup.

How can you prevent your air conditioning system from freezing up?

Regularly clean the condenser coils and replace dirty furnace filters. If your system freezes, immediately turn it off and switch the fan to 'on' to help thaw the ice. If the issue persists, check for refrigerant leaks or faulty components.

What causes water to leak around the furnace despite the AC cooling properly?

A clogged condensate drain is the likely cause of water leakage around the furnace. If the drain is blocked, water backs up and leaks out, even if the AC is cooling the air properly.

How do you fix a clogged condensate drain?

To fix a clogged condensate drain, disconnect the hose or fitting and clean it out. You can blow air through the fitting or clear the blockage manually to restore proper drainage.

What are the signs of a faulty control board in an AC system?

Signs of a faulty control board include the AC not turning on, the furnace running simultaneously with the AC, or the blower motor failing to operate. A malfunctioning control board can prevent the system from functioning properly.

What should you do if the AC compressor overheats and trips the breaker?

If the AC compressor overheats and trips the breaker, the issue may be with a burnt-out condenser fan motor or faulty wiring. Check the fan motor, capacitor, and wiring for any damage, and replace the necessary parts.

What should be done if a mouse damages the AC unit?

If mice have chewed through the wires or created a nest inside the AC unit, it is important to remove the nest, check for damaged wires, and replace any damaged components to ensure proper operation.

What is the best type of furnace filter to use?

The best furnace filter is a medium-grade pleated filter. It provides a balance between filtration efficiency and airflow. Avoid filters that are too restrictive or too flimsy, as they can either clog too quickly or allow debris to pass through.

How can you tell if an AC unit is completely out of refrigerant?

If an AC unit is completely out of refrigerant, it will show signs of being in a vacuum state, with no cool air coming from the vents. This often indicates a large leak in the system that requires immediate repair.

What should you do if the AC unit’s circuit breaker keeps tripping?

If the AC circuit breaker keeps tripping, it could indicate a short circuit or damaged wiring. Check for melted wires, faulty components like the compressor or contactor, and repair or replace as necessary.