U-Line SP 18 - Frost Free Refrigeration; COOLING MODE; DEFROST MODE

3-2
Section 3 - Service and Repair
Frost Free Refrigeration
COOLING MODE
• Bypass solenoid closed.
• Evaporator fan operating.
• Refrigerant flows through capillary tubes.
• Normal vapor/compression cycle refrigeration (see page 3-
1).
DEFROST MODE
• Bypass solenoid valve open.
• Refrigerant flows through bypass system.
• Vapor flows from condenser to evaporator without a
phase change.
• Drain heater on (U-CO29F only).
Figure 2. Frost Free Refrigeration System.
•
SOLENOID VALVE
CAPILLARY TUBE
VALVE IS CLOSED
FLOW WHEN SOLENOID
DRYER
CONDENSER
COMPRESSOR
EVAPORATOR
VALVE IS OPEN
FLOW WHEN SOLENOID
ULIN_0369_A