Purpose: To identify units that have recently developed a leak and have lost refrigerant.
1. Operate the unit on high speed cool 5 to 10 minutes.
2. Refrigerant should be present in the sight glass.
3. If the sight glass is empty, cover the condenser and operate the unit in high speed cool for 1 to 3 minutes.
4. Check the receiver tank sight glass:
a. If refrigerant is visible in sight glass – charge is sufficient for present box temperature.
b. If no refrigerant is visible in the sight glass – unit may have a leak and lost charge. See “Controlled Refrigerant Level Check” on page 16.
