Refrigerant is not a consumable. It circulates in a sealed loop and stays there for the life of the equipment unless something breaches that loop. A system that is low on charge has a leak, and locating it is the actual repair work.
Because charge loss is usually gradual, refrigerant leaks tend to present as cooling that quietly gets worse across a season rather than as a sudden breakdown. Homeowners often adapt to it — lowering the thermostat, adding fans — before recognizing it as a fault.
Simply adding refrigerant without addressing the breach returns the system to the same condition it was in before, on a timeline set by the size of the leak. It also releases regulated refrigerant into the atmosphere and can mask a developing problem that will eventually reach the compressor.
No single symptom confirms a leak, but several together make it a strong candidate for investigation.
Evaporator coils are a frequent origin, particularly formicary corrosion, which produces microscopic pinholes in copper tubing over years of exposure to indoor air contaminants. Condenser coils in coastal environments corrode from the outside in as salt aerosol settles into the fin pack.
Other common locations include brazed joints, service valve cores and caps, vibration-fatigued suction lines, and line-set penetrations where copper rubs against a structural surface. Accessible joint leaks are generally the most straightforward to repair; coil leaks often are not.
Leak location is a methodical process. Electronic detectors sweep suspected areas, bubble solution confirms candidate joints, and ultraviolet dye circulated through the system reveals slow leaks that are difficult to catch in a single visit.
Where the leak cannot be found under normal operation, a nitrogen pressure test isolates sections of the circuit and identifies which one loses pressure. Very small leaks sometimes require a return visit after a dye has had time to travel, which is a normal part of the process rather than an inconclusive result.
A leak at an accessible joint or valve can often be repaired directly. A coil riddled with corrosion pinholes usually cannot be reliably sealed, because sealing one pinhole does nothing about the ones forming next to it, and coil replacement becomes the durable option.
Sealant additives marketed as leak stops are viewed cautiously in the trade, since they can interfere with metering devices and complicate future service work on the sealed system.
Once the circuit is sealed, the repair is not finished. Air and moisture that entered during the leak or the repair must be removed by pulling a deep vacuum, because moisture inside a refrigeration circuit forms acids that attack the compressor over time.
The system is then charged by weight to the manufacturer's specification and verified with superheat or subcooling measurements appropriate to the metering device. Charging by pressure alone, without those measurements, is a common source of systems that remain slightly off after service.
Equipment using refrigerants that are no longer produced faces a supply-driven cost problem. When a major leak appears in one of those systems, the comparison between repairing and replacing shifts, because the refrigerant itself may represent a significant share of the repair.
Newer equipment also uses refrigerants with different pressure characteristics, so a like-for-like conversion is generally not possible. This is worth understanding before deciding how much to invest in an aging unit.
The system runs, the house stays warm — the possible causes and what a diagnosis examines.
Why coils freeze in hot weather, what to do first, and what a diagnosis examines.
What the compressor does, what mimics its failure, and how repair compares to replacement.
Not sure which of these matches your system? Start with the AC problems overview or read how repair pricing is put together on the AC repair cost page. You can also see the Port St. Lucie areas covered.
Common residential refrigerants are low in toxicity in ventilated spaces, so the primary concerns are equipment damage and lost capacity rather than health. Poor ventilation and large releases are a different situation and should be treated seriously.
It depends entirely on the size of the breach. A pinhole may take a full season to become noticeable, while a failed joint can empty a system in hours.
Sometimes. Joint, valve, and line-set leaks are often repairable. Widespread corrosion pinholes across a coil generally are not, because the underlying condition affects the whole component.
Moisture in a sealed system combines with refrigerant and oil to form acids that degrade internal components. Evacuation removes that moisture along with non-condensable air before the system is charged.
If the leak was the limiting factor and the rest of the system is sound, capacity typically returns once the correct charge is in place and verified by measurement.
Call 772-946-1295 to describe what your system is doing, or send a service request and we will follow up to arrange a visit.
