Cincinnati Sub-Zero ZP Series - Page 85

MAINTENANCE WITH Q & A
73
LN2 BOOST COOLING TROUBLESHOOTING PROCEDURES (OPTIONAL EQUIPMENT)
PROBLEM
PROBABLE CAUSE
CORRECTIVE ACTION
No LN2 Flow
Check LN2 Supply
Is the LN2 Supply tank empty?
Check solenoid valves
Are the solenoid valves opening?
Do the solenoid coils have power? They should have 120 VAC
applied to the coil.
Table 5-7: LN2 System Troubleshooting Procedures
GN2 SYSTEM TROUBLESHOOTING PROCEDURES (OPTIONAL EQUIPMENT)
PROBLEM
PROBABLE CAUSE
CORRECTIVE ACTION
Unit doesn't reach
low humidity
setpoint
Solenoid core spring not
seated properly or is
broken
Remove solenoid valve. Spring should be seated on core and
not broken. R
eplace if necessary.
Solenoid coil burned out
Remove cover, place iron or steel material (screwdriver or
nail) on exposed end of solenoid base to feel the magnetic
effect indicating proper
operation. Each coil should be
energized for 30 seconds. Depres
s switch lever by hand and
listen for clicking contact. Switch should click when
depressed and when released. Replace if necessary.
Excessive drop in
outlet pressure
Solenoid coil burned out
Remove cover, place iron or steel material (screwdriver or
nai
l) on exposed end of solenoid base to feel the magnetic
effect indicating proper operation. Each coil should be
energized for 30 seconds. Depress switch lever by hand and
listen for
clicking contact. Switch should click when
depressed and when released. Replace if necessary.
Solenoid valve
chatter
Solenoid valve defective
Replace solenoid valve core assembly and solenoid base.
Table 5-8: GN2 Troubleshooting Procedures
GN2/LN2 can displace
oxygen and become a
hazard in an enclosed area.
WARNING