Signs of a Refrigerant Leak in Your AC System

What Is Refrigerant?

Refrigerant is the chemical compound that cycles through your AC system, absorbing heat from indoor air and releasing it outside. Modern systems use R-410A (Puron) or the newer R-454B. Older systems may use R-22 (Freon), which has been phased out due to environmental concerns — making leaks in older systems particularly expensive to address.

Warning Signs of a Refrigerant Leak

• Warm air from vents — AC runs but doesn't cool effectively
• Ice on refrigerant lines or coils — paradoxically, low refrigerant causes freezing
• Hissing or bubbling sounds — indicates gas escaping from the refrigerant circuit
• Higher electricity bills — system runs longer to achieve setpoint temperature
• Longer cooling cycles — the system struggles and runs continuously
• Oily residue near connections — refrigerant oil leaks out with refrigerant gas

Why Simply "Topping Off" Refrigerant Is Wrong

Refrigerant is a closed-loop system — it doesn't get consumed. Low refrigerant always means a leak. Adding refrigerant without fixing the leak is an expensive temporary fix that damages the compressor over time and releases refrigerant into the atmosphere (which is both environmentally harmful and federally regulated).

What to Do

Turn off your AC (let ice thaw if frozen), and call Chicago Service HVAC. We'll locate and repair the leak using electronic leak detectors, recharge to the correct specification, and verify system performance. All refrigerant handling is performed by EPA 608-certified technicians.