Troubleshooting
173
Liebert
®
CRV
™
Capacity Reduced
due to HP Alarm
(Comp Reduced by
HP)
Condensing pressure (head pressure) has
exceeded 493 psig (34 bar)
Air-cooled units: Verify that remote condenser fan(s) are
running
Check accuracy of transducer by attaching a manifold
gauge to discharge side of compressor. Compare gauge
reading to what is shown in Service Menus, Diagnostic
service mode.
Water/glycol units: Check cooling water supply
Water/glycol units: Check cooling water temp
Contact Emerson Network Power
Digital Scroll
Sensor Failure
Sensor disconnected
Verify sensor reading in User Menu, Sensor Data.
Check plug connections
Contact your local Emerson representative
Low Supply
Temperature Alarm/
Room Overcooling
Low return temperature
Place a unit into standby (if applicable)
Poor airflow
Install blanking panels in open areas of racks. Consult your
local Emerson representative.
Direct discharge baffles to heat source
Supply chilled water temperature too low. Check cooling water temperature
Low Room
Humidity
Humidifier Suspended message.
See
Humidifier problem alarm.
Check fault LED on humidifier PCB enclosure.
See
A.1.6 Humidifier Troubleshooting
Room Humidity Problem
Room humidity has exceeded the humidity control band
for 36 hours straight. Verify setpoints and confirm room is
properly sealed.
High Room
Humidity
Dehum Suspended message
The operated in dehumidification for excessive time.
Dehumidifcation is suspended to prevent condensation for
forming on accent panels and other areas.
Room Humidity Problem
Room humidity has been below the humidity control band
for 36 hours straight. Verify setpoints and confirm room is
properly sealed.
Unit fan fails
to start
Fan is faulty
Contact your local Emerson representative
Top or Bottom Fan Failure Alarm
Confirm rear door switches are made
Confirm fan contactor is pulled in
Confirm line voltage is present at the fan
Contact your local Emerson representative
Table 40
Unit diagnostics
Problem
Possible Cause
Corrective Action