Emerson Liebert CRV - Liebert CRV Troubleshooting Guide; Rack Temperature Issues; Evaporator Fan Modulation Problems

Troubleshooting
Liebert
®
CRV
™
172
17.0 TROUBLESHOOTING
Table 40 Unit diagnostics
Problem Possible Cause Corrective Action
Rack temperature
is too high
Dirty filters Replace filters
Filter clog sensor failure Call Emerson Network Power
®
Incorrect positioning of remote
temperature sensor(s)
Verify that remote temperature sensors are correctly
positioned
Remote temperature sensor(s) issue
Verify CANbus cable connections and CANbus termination
are correct.
Adjust remote sensor mode(max/average) and number of
sensors calculated in average.
Contact your local Emerson representative
Chilled water units: inlet water
temperature is too high
Check cooling water temperature
Refrigerating circuit charge issue Contact your local Emerson representative
Cold air short-cycling issues
Verify unit positioning/room configuration
Verify unit air baffles set-up
Verify cold aisle containment seals (if applicable)
Insufficient room-cooling capacity Reduce rack heat load or add cooling units
Chilled water-regulating valve issue Contact your local Emerson representative
Unit safety device tripped Contact your local Emerson representative
Compressor will not load
Verify air temperature setpoint and temperature control
sensor reading
Verify suction pressure in the service menus, diagnostic
service icon with the compressor loaded to 100%. If the
suction drops below 109 psi (7.5 bar), the compressor
capacity will decrease to help build suction. Verify suction
transducer reading is correct compared with a manifold
gauge.
Evaporator Fans
will not modulate
from 100%
Low pressure condition detected
Verify suction pressure in the service menus, diagnostic
service icon with the compressor loaded to 100%. If the
suction drops below 109 psi (7.5 bar), the fan speed will
increase to help build suction. Verify suction transducer
reading is correct compared with a manifold gauge.
Contact your local Emerson representative
Fan control not properly set
See 11.3 Liebert CRV Operation—Liebert iCOM Control
Contact your local Emerson representative