Refrigerant does not get used up through normal operation. If cooling gradually weakens, the sealed system usually has a leak rather than simply needing a routine refill.
The Telltale Pattern
- Cooling is weaker but not completely absent
- Cooling fades after ten to fifteen minutes
- Performance is worse in slow traffic than at highway speed
- A faint hissing or chemical smell appears near the vents or fittings
Common Leak Points
- O-ring seals at hose and component connections