How to Detect a Refrigerant Leak

Refrigerant is the magic ingredient that makes your air conditioner work. It absorbs warm indoor air, then transforms from a liquid to a gas to release that heat outside. This cycle repeats until your home reaches the set temperature.

When refrigerant leaks, the process is disrupted – and it can even pose safety risks. Here’s how to spot the most common signs of a leak and detect it before it causes bigger problems.

Signs of a Refrigerant Leak

• Reduced Cooling Performance. When refrigerant escapes, your AC struggles to cool your home effectively. It may take much longer to reach the set temperature, or it may never get there.
• Lukewarm Air. If your AC is running but the air coming from the vents feels warm, it’s often a sign of a refrigerant leak. Enough refrigerant may have escaped to prevent the system from cooling at all.
• Higher Energy Bills. A refrigerant leak can cause your AC to run constantly as it tries – often unsuccessfully – to keep up with cooling demand. This drives up your energy costs.
• High Humidity. Low refrigerant levels also reduce your air conditioner’s ability to remove moisture from the air, leaving your home feeling damp or stuffy.

How to Detect a Refrigerant Leak

Because refrigerant can be harmful if inhaled – potentially leading to health effects like dizziness, headaches, and nausea – it’s important to contact a reputable HVAC professional for any repairs. They have the proper tools to locate and fix leaks safely.

If you’re unsure whether you have a leak, here are a few simple troubleshooting tips you can try:

Listen for Leaks

Stand near the refrigerant lines outside and listen for a hissing or bubbling sound. This happens when pressurized refrigerant escapes through a small hole or crack, rapidly changing from a high-pressure liquid to a gas.

Look for Visual Clues

Check refrigerant lines, coils, and connections for oily spots or residue, as leaking refrigerant often carries compressor oil with it. You might also see frost or ice buildup on the evaporator coil or lines, which can indicate low refrigerant levels.

Use Soap and Water

Fill a spray bottle with soap and water, then spray it on the refrigerant lines. If you see bubbles forming, refrigerant may be escaping. Keep in mind that tiny “pinhole” leaks might not produce bubbles, so a professional inspection is still recommended.

What Causes Refrigerant Leaks?

Common causes include:

• Corrosion of the copper refrigerant lines.
• Wear and tear that degrades rubber seals around valves and connections.
• Improper installation, which can create weak points.
• Physical damage from animals, debris, or lawn equipment.

How to Prevent a Refrigerant Leak

Regular HVAC maintenance is the best defense against refrigerant leaks. During a tune-up, a technician will inspect refrigerant lines for signs of wear, check connections and fittings for tightness, and make sure the system’s pressure levels are within the proper range. 

They’ll also clean coils and remove debris that could cause corrosion over time. By catching small issues early, maintenance helps prevent the kind of damage that can lead to costly and dangerous refrigerant leaks.