Troubleshooting Guides
Under Counter (UC-24) Series
8-15
#7003933 - Revision B - November, 2007
UC-24C
5” Vac - 1 psi to 6 - 12 psi 75 psi to 120 psi
UC-24R / UC-24RO
0 - 12 psi to 30 - 42 psi 75 psi to 110 psi
SEALED SYSTEM DIAGNOSTICS TABLES
NORMAL OPERATING PRESSURES TABLE NOTES:
• Only enter the sealed system to check pressures if the Error Code Troubleshooting Guide and General
Troubleshooting Guide could not pinpoint the cause of the temperature problem.
• Always use solder-on process valves when entering the sealed system. Do NOT use bolt-on process valves as
they are prone to leak.
• Whenever servicing the sealed system, the high-side filter-drier MUST be replaced.
• Pressures listed below are not indicative of initial pull down, but rather of a steadily running and properly function-
ing appliance.
• Pressures listed are for reference only, as actual pressure readings may vary because of one or more of the fol-
lowing reasons:
1. Ambient temperatures (Pressures are based on a 70°F (21°C) Ambient).
2. Temperature set-points (Pressures listed below are based on set-points of 0°F (-18°C) in freezers and 38°F
(3°C) in refrigerators)
3. Food load quantity and temperature.
4. Condenser cleanliness.
5. Whether or not one or both refrigeration systems are operating.
6. Gauge calibration.
NORMAL OPERATING PRESSURES
Model Normal Low-Side Pressures Normal High-Side Pressures
UC-24B
0 - 12 psi to 30 - 42 psi 75 psi to 110 psi
PRESSURE INDICATIONS
If low-side pressure is
NORMAL
LOW
LOW
HIGH
HIGH
& high-side pressure is
NORMAL
LOW
HIGH
LOW
HIGH
possible problem is
MECHANICAL
(see General Troubleshooting Guide)
LEAK
RESTRICTION
INEFFICIENT COMPRESSOR
OVER CHARGE