Troubleshooting (To Be Performed By Trained Service Providers Only); Evaporator System - Structural Concepts BLEND NM4855RSSV User Manual

TROUBLESHOOTING (BY TRAINED SERVICE PROVIDERS ONLY) - EVAPORATOR SYSTEM
CONDITION
Low Suction Check if sight glass is flashing or showing low charge.
Pressure
Check that expansion valve (TXV) isn't restricted. Check element charge.
Check that liquid line or filter isn't restricted. Check that refrigeration lines and/or
hoses are not kinked on either high or low sides.
Check that evaporator fan motors are working.
Check that superheat is between 6 °F to 8 °F.
Check that there is no air recirculation around evaporator coil.
Check that evaporator coil is not iced up.
High Suction Check for refrigerant overcharge.
Pressure
Check that compressor reed valves aren't bad. Look for high suction/low head
pressure. Perform pump down.
Check that the "cooling load" isn't high. Product must be pre-chilled before placing in
refrigerated section of case.
Check that case is at least 15-feet from exterior doors, overhead HVAC vents or any
air curtain disruption.
Check that unit is not exposed to direct sunlight via windows or any other heat source
(ovens, fryers, etc.).
Check that superheat adjustment isn't low.
Check TXV bulb installation
a. Poor thermal contact.
b. Warm location.
TROUBLESHOOTING
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