The function of failures determination is stored in the Carrier air conditioner program. The system is able to correct some violations itself, but it does not help at all times. Therefore, it is desirable to have a manual containing error codes decoding at hand. It is presented below in form of a table.
Air conditioners from the Carrier GEMINI 38APD025-100 range belong to commercial lineup, and therefore, are excellent for restaurants, hotels, government buildings etc. 38AP air-cooled condensing unit boasts Comfortlink™ electronic system controls. The system composed of several elements is responsible for controlling and monitoring all operations of the unit.
| ALARM/ ALERT CODE | DESCRIPTION | WHY WAS THIS ALARM GENERATED? |
|---|---|---|
| T048 | Circuit A Compressor Availability Alert | Two compressors on circuit failed |
| T049 | Circuit B Compressor Availability Alert | Two compressors on circuit failed |
| T051.T052, T053 | Circuit A Compressor A1 .A2.A3 Failure | Respective current sensor board (CSB) feedback signal does not match relay state |
| TOSS, T056, T057 | Circuit B Compressor B1 .B2.B3 Failure | Respective current sensor board (CSB) feedback signal does not match relay state |
| A051, A052, A053 | Circuit A Compressor A1 .A2.A3 Failure | Respective current sensor board (CSB) feedback signal is ON when the compressor should be off |
| A055, A056, A057 | Circuit B Compressor B1 .B2.B3 Failure | Respective current sensor board (CSB) feedback signal is ON when the compressor should be off |
| A060 | Supply Air Thermistor Failure | Thermistor outside range of -40 to 245 F (-40 to 118 C) |
| A060 | Supply Air Temperature Update not received | Temperature not updated during 3 minutes |
| A061 | Return Air Thermistor Failure | Thermistor outside range of -40 to 245 F (-40 to 118 C) |
| A061 | Return Air Temperature Update not received | Temperature not updated during 3 minutes |
| T068 | Circuit A Return Gas Thermistor Failure | Thermistor is outside range of -40 to 245 F (-40 to 118 C) |
| T069 | Circuit B Return Gas Thermistor Failure | Thermistor is outside range of -40 to 245 F (-40 to 118 C) |
| T073 | Outside Air Thermistor Failure | Thermistor outside range of -40 to 245 F (-40 to 118 C) |
| T074 | Space Temperature Thermistor Failure | Thermistor outside range of -40 to 245 F (-40 to 118 C) |
| T090 | Circuit A Discharge Pres- sure Transducer Failure | The pressure is outside the range of 0.0 to 667.0 psig |
| T091 | Circuit B Discharge Pres- sure Transducer Failure | The pressure is outside the range of 0.0 to 667.0 psig |
| T092 | Circuit A Suction Pressure Transducer Failure | The pressure is outside the range of 0.0 to 420.0 psig |
| T093 | Circuit B Suction Pressure Transducer Failure | The pressure is outside the range of 0.0 to 420.0 psig |
| T094 | Discharge Gas Thermistor Failure | Discharge thermistor (DTT) is either open or shorted |
| T110 | Circuit A Loss of Charge | If the compressors are off and discharge pressure reading is less than 26 psig for 30 sec. |
| T111 | Circuit B Loss of Charge | If the compressors are off and discharge pressure reading is less than 26 psig for 30 sec. |
| T112 | Circuit A High Saturated Suction Temperature | Circuit is on and saturated suction temperature is greater than 70 F (15.6 C) for 5 minutes |
| T113 | Circuit B High Saturated Suction Temperature | Circuit is on and saturated suction temperature is greater than 70 F (15.6 C) for 5 minutes |
| T114 | Circuit A Low Suction Superheat | Suction superheat is less than 5 F (2.8 C) for 5 minutes. |
| T115 | Circuit B Low Suction Superheat | Suction superheat is less than 5 F (2.8 C) for 5 minutes. |
| T118 | High Discharge Gas Temperature | Discharge Thermistor (DTT) reading is greater than 250 F |
| A118 | High Discharge Gas Temperature | 3 Discharge Gas Temperature alarms occur within a day |
| P120 | Circuit A Low Saturated Suction | SSTA is less than 20 F for 4 minutes, less than 10 F for 2 minutes, less than 0° F for 1 minute or less than -20 F for 20 seconds continuously |
| T120 | Circuit A Low Saturated Suction | SSTA is less than 20 F for 4 minutes, less than 10 F for 2 minutes, less than 0° F for 1 minute or less than -20 F for 20 seconds continuously |
| A120 | Circuit A Low Saturated Suction | SSTA is less than 20 F for 4 minutes, less than 10 F for 2 minutes, less than 0° F for 1 minute or less than -20 F for 20 seconds continuously and only one compressor running |
| P121 | Circuit A Low Saturated Suction | SSTB is less than 20 F for 4 minutes, less than 10 F for 2 minutes, less than 0° F for 1 minute or less than -20 F for 20 seconds continuously |
| T121 | Circuit B Low Saturated Suction | SSTB is less than 20 F for 4 minutes, less than 10 F for 2 minutes, less than 0° F for 1 minute or less than -20 F for 20 seconds continuously and only one compressor running |
| A121 | Circuit B Low Saturated Suction | SSTB is less than 20 F for 4 minutes, less than 10 F for 2 minutes, less than 0° F for 1 minute or less than -20 F for 20 seconds continuously and only one compressor running |
| T122 | High Pressure Switch Trip Circuit A | High Pressure A Switch Input open to MBB |
| T123 | High Pressure Switch Trip Circuit B | High Pressure B Switch Input open to MBB |
| T126 | Circuit A High Discharge Pressure | SCTA >150 F |
| A126 | Circuit A High Discharge Pressure | SCTA >150 F |
| T127 | Circuit B High Discharge Pressure | SCTB >150 F |
| A127 | Circuit B High Discharge Pressure | SCTB >150 F |
| A140 | Reverse Rotation Detected | Incoming unit power leads not phased correctly |
| A150 | Emergency Stop | CCN emergency stop command received |
| A151 | Illegal Configuration | One or more illegal configurations exists. |
| T153 | Real Time Clock Hardware Failure | Internal clock on MBB fails |
| A154 | Serial EEPROM Hardware Failure | Hardware failure with MBB |
| T155 | Serial EEPROM Storage Failure | Configuration/storage failure with MBB |
| A156 | Critical Serial EEPROM Storage Failure | Configuration/storage failure with MBB |
| A157 | A/D Hardware Failure | Hardware failure with peripheral device |
| A170 | Loss of Communication with CXB | MBB loses communication with CXB |
| A173 | Loss of Communication with EMM | MBB loses communication with EMM |
| T174 | 4 to 20 mA Cooling Set Point/Desired % Capacity Input Failure | If configured with EMM and input less than 2 mA or greater than 22 mA |
| T176 | 4 to 20 mA Temperature Reset Input Failure | If configured with EMM and input less than 2 mA or greater than 22 mA |
| T177 | 4 to 20 mA Demand Limit Input Failure | If configured with EMM and input less than 2 mA or greater than 22 mA |
| A200 | Fan Status Switch 1 Open | Alarm is generated when fan status switch 1 is open when the unit is in an ON state |
| T201 | Fan Status Switch 1 is open with Dual TSTAT configuration | Alert is generated when fan status switch 1 is open when Y1 or Y2 are closed |
| T202 | Fan Status Switch 2 is open with Dual TSTAT configuration | Alert is generated when fan status switch 1 is open when Y3 or Y4 are closed |
| T303 | Condenser Coil Maintenance Due | Coil Service Countdown (C.L.DN) expired. Complete condenser coil cleaning and enter 'YES’ for Coil Maintenance Done (C.L.MN) item. |
| T500 | Current Sensor Board A1 Failure | Alert occurs when CSB output is a constant high value |
| T501 | Current Sensor Board A2 Failure | Alert occurs when CSB output is a constant high value |
| T502 | Current Sensor Board A3 Failure | Alert occurs when CSB output is a constant high value |
| T503 | Current Sensor Board B1 Failure | Alert occurs when CSB output is a constant high value |
| T504 | Current Sensor Board B2 Failure | Alert occurs when CSB output is a constant high value |
| T505 | Current Sensor Board B3 Failure | Alert occurs when CSB output is a constant high value |
Carrier MOTORMASTER 4850P3 is a motor speed control device for 48/50P030-100 units. It makes the operating range of air conditioners wider and allows you to use your air conditioner at lower outdoor ambient temperatures. Should the device break down, you may try fixing it on your own using the error codes from the tables below.
| CODE | DESCRIPTION | PROBABLE CAUSE |
|---|---|---|
| AF | High Temperature Fault | Ambient temperature is too high; Cooling fan has failed (if equipped). |
| CF | Control Fault | A blank EPM, or an EPM with corrupted data has been installed. |
| cF | Incompatibility Fault | An EPM with an incompatible parameter version has been installed. |
| F1 | EPM Fault | The EPM is missing or damaged. |
| F2—F9 Fo | Internal Faults | The control board has sensed a problem |
| GF | Data Fault | User data and Carrier defaults in the EPM are corrupted. |
| HF | High DC Bus Voltage Fault | Line voltage is too high; Deceleration rate is too fast; Overhauling load. |
| JF | Serial Fault | The watchdog timer has timed out, indicating that the serial link has been lost. |
| LF | Low DC Bus Voltage Fault | Line voltage is too low. |
| OF | Output Transistor Fault | Phase to phase or phase to ground short circuit on the output; Failed output transistor; Boost settings are too high; Acceleration rate is too fast. |
| PF | Current Overload Fault | VFD is undersized for the application; Mechanical problem with the driven equipment. |
| SF | Single-phase Fault | Single-phase input power has been applied to a three-phase drive. |
| Drive displays “—“ even though drive should be running | Start Contact is Not Closed | Start contact is missing or not functioning. |
| VFD flashes “---” and LCS | Start Contact is Not Closed | Start contact not closed. |
| VFD flashes 57 (or 47) and LCS | Speed Signal Lost | Speed signal lost. Drive will operate at 57 (or 47) Hz until reset or loss of start command. Resetting requires cycling start command (or power). |