Carrier 48FK, JK034-074, 50FK Operation Status Codes, Controls Troubleshooting, Code Meaning

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TROUBLESHOOTING

By using the display module, actual operating conditions of the unit are displayed while it is running. The Quick Test function allows proper operation of compressors, compres- sor unloaders, fans, and other components to be checked while unit is stopped. If an operating fault is detected, an alarm is generated and an alarm code(s) is displayed. For checking speci®c items, see Table 20.

Checking Display Codes Ð To view the digital dis- play codes, press the button located to the right of the LED display/set point board in the control box. See Table 21 for Operational Status Codes. See Table 22 for Diagnostic Codes.

Complete Unit Stoppage Ð If the unit is off, there are several conditions that can cause this situation to occur:

·Remote ON/OFF circuit in Unoccupied mode.

·Unit ON/OFF switch moved to OFF position.

·Programmed schedule at the timeclock.

·General power failure.

·Blown fuse in the control power feed.

·Open control circuit fuse.

·Operation of the unit blocked by the demand limit function.

·Unit supply-air temperature (T1) thermistor failure.

·Supply-air fan is not operating.

·High duct static pressure.

Single Circuit Stoppage Ð If a single circuit stops, there are several potential causes:

·Open contacts in the compressor high-pressure switch.

·Low refrigerant pressure.

·Thermistor failure.

·Unit supply-air temperature thermistor (T1) failure.

·Compressor circuit breaker trip.

·Operation of the circuit blocked by the demand limit function.

Table 21 Ð Operation Status Codes

CODE

MEANING

0

0 cooling stages active

 

 

1

1 cooling stage active

 

 

2

2 cooling stages active

 

 

3

3 cooling stages active

 

 

4

4 cooling stages active

 

 

5

5 cooling stages active

 

 

6

6 cooling stages active

 

 

7

7 cooling stages active

 

 

8

8 cooling stages active

 

 

 

Initialization mode (Allow 2 minutes

20

for initialization. To initiate Quick Test,

 

press the Display button while 20 is displayed.)

21

Temperature Reset in effect

 

 

22

Demand Limit in effect

 

 

26

Morning Warm-Up in effect

 

 

30

Internal failure detected

 

 

88

Self-diagnostic mode in effect

 

 

Restart Procedure Ð Before attempting to restart the machine, check the display for alarm codes to determine the cause of the shutdown. If the unit, circuit, or compressor stops more than once as a result of a safety device, determine and correct the cause before attempting to start the unit again.

After the cause of the shutdown has been corrected, unit restart may be automatic or manual depending upon the fault.

Table 20 Ð Controls Troubleshooting

SYMPTOM(S)

 

PROBABLE CAUSE(S)

 

SOLUTION(S)

Controls do not seem

Remote on-off function may be

Check status.

to be operating.

keeping controls off.

 

 

Evaporator fan does not run.

1.

Circuit breaker open.

1.

Find cause and reset circuit breaker.

 

2.

Inverter overload (if equipped).

2.

Find cause and reset.

Compressor does not run.

1.

Circuit breaker is open.

1.

Find cause and reset circuit breaker.

 

2.

There is no demand for cooling.

2.

Correct operation.

 

3.

The control is locking out cooling operation.

3.

Check rotating display for alarm codes. Resolve

 

 

 

 

alarm cause and reset control by changing to

 

 

 

 

standby and back to run mode.

 

4.

Demand Limit in effect.

4.

Check Demand Limit Settings.

Condenser fans do not

Circuit breaker is open.

Find cause and reset circuit breaker

turn on.

 

 

 

 

Cooling demand exists and

Compression cannot be initiated

Correct operation.

economizer modulates, but

until economizer damper is 90% open.

 

 

compression is not operating.

 

 

 

 

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Contents Controls Operation Troubleshooting ContentsSafety Considerations GeneralPin Terminal Connector J1 Thermistor Inputs Connector J1 Temperature Unit Size Terminal no InputDIP EXVStatus Switch Inputs Connector J2 Status Switch Unit Size Terminal no034-104 RNT Ð ReturnPage Output Pin and Terminal Assignments Output PIN Name Rating Device TerminalHIR IFCCompressor Operation Thermistor T1 Location, 50FK,JK034-048 Units Thermistor T1 Location, 50FK,JK054-074 Units Thermistor T2 Location, Size 034-048 Units Thermistor T3 and T4 Locations, Size 054-104 Units Integrated Circuit InputControls Installation Space Temperature ResetUnit Control Box Arrangement, Sizes Unit Control Box Arrangement, Sizes Unit Control Box Arrangement, Sizes 088 Voltage Drop Characteristics Thermistor ResistanceSpace Temperature Sensor Averaging Single-Step Demand Limit MSP = Sasp + Remote Sasp Wiring Smoke Control Switches Required for Each Mode Smoke Control ModesSwitch Functions Tubing SizeTerminal Block DPS Ð Differential Pressure SwitchSwitch Modulating Power Exhaust Differential Pressure Switch Sizes START-UPConguration Header Jumpers Conguration Header DIP Switch Factory SettingsPotentiometer Inputs and Ranges DIP Switches Switch Function Meaning PositionInlet Guide Vane Motor 50FK,JK034-074 Units Jumper Removal to Disable Motor Variable Frequency Drive KeypadVFD Set Point Frequency Command for Duct Pressure Changing the VFD Set Point Frequency CommandControl Signal Pressure VFD SET Point PressureStart Unit Quick Test, Unit Conguration and Switch Check Quick Normal Description Control Switch Test Display Step noQuick Test, Thermistor and Potentiometer Check Quick Test, Output Relay CheckQuick Normal Description Thermistor or Test Quick Normal Test Description Relay NumberOperating Information Sensor Resistance ValuesPage Component Arrangement, 034-048 Units Component Arrangement, 054-104 Units Page Modulating Power Exhaust Component Locations Sizes Modulating Power Exhaust Component Locations Sizes Page Compressor Loading and Unloading Sequences Cooling Size 054 Units Cooling Size 064 UnitsCooling Size 088 Units Cooling Size 104 UnitsTroubleshooting Controls TroubleshootingSymptoms Probable Causes Solutions Operation Status CodesDiagnostic Codes Codes 71 to 76 THERMISTOR/RESISTOR Failure Page Terminals Voltage AC Test PIN Voltage DC TP3TP4 TP6Quick Test J9 PIN Numbers Step no PIN Terminal Voltage DCPin Terminal Connector J1 Voltages Pin Terminal Connector J2 VoltagesTerminal Strip J6 Connection Resistance Reading PIN Voltage TerminalQuick Test J5 PIN Numbers Step no Terminal Strip J5 Connector Resistance ReadingEnthalpy Sensor Checkout Variable Frequency Drive Carrier Default Program Parameter Values Parameter Group Default ValueRequired User Adjusted Defaults Motor Overload SettingsALM LATLPS MTRPage Page Service Training Call for Free CatalogII. Preliminary Checklist Items PRE-START-UPIII. START-UP IV. Notes