Carrier 69NT40-489-100 Series, Operation And Service Manual

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115
T-305
SECTION 11
TROUBLESHOOTING
NOTE
This troubleshooting chart is to be used with Controlled Atmosphere sections only.
INDICATION/
TROUBLE
POSSIBLE CAUSES
REMEDY/
REFERENCE
SECTION
11.1 CONTROLLED ATMOSPHERE (CA) SYSTEM WILL NOT START
No power to unit
External power source OFF Turn on
Start-Stop switch (CAS) OFF or defective Check/Replace
Loss of control power
Fuse blown (F3) Check
Start-Stop switch (CAS) OFF or defective Check/Replace
Loss of control power in
respective branch of control
circuit only
Air compressor internal protector (IP-AM) open Check
High pressure switch (HATS) open Check
Air compressor hums, but does
not start
Low line voltage Check
Single phasing Check
Shorted or grounded motor windings Check
Air compressor seized Check
11.2 CONTROLLED ATMOSPHERE (CA) SYSTEM MALFUNCTION
Air compressor will not start
Temperature Controller not configured for CA Check
CA in STANDBY mode Check
External power source OFF Turn on
Air compressor contactor (AC) defective Replace
Internal protector (IP-AM) open Replace
Unit at set point Check
Unit in Pre-trip (Temperature Controller) Check
Air compressor runs, oxygen %
will not come down
Air compressor off more than 3 minutes Check
Leaky cylinder head o-ring Check
Leaky discharge manifold assembly Check
Leaky air solenoid valve (ASV) Check
Sensor defective Check
Membrane defective Check
Heater defective Check
Oxygen solenoid valve (OSV) defective Check/Replace
Heater malfunction
Membrane temperature sensor failure Replace
Heating element defective Check
Contactor defective (AH) Check
Solid State Relay (SSR) defective (AT) Check
CA in STANDBY mode (refer to section 10.2) Check
High air temperature switch failure Replace