Samsung AQ30C2BC - User Manual

Questions and Answers

K
Katherine PattonAug 18, 2025
How to understand STD operation indication LED behavior on a Samsung AQ30C2BC Air Conditioner?
- L
  Lauren BurtonAug 18, 2025
  The blinking STD operation LED indicates that the power is on. To stop the LED from blinking, press the operation ON/OFF button on the remote control.
L
leejasonAug 21, 2025
Why does my Samsung AQ30C2BC compressor stop intermittently in COOL or DRY mode and the fan speed decreases?
- L
  Lisa TerryAug 21, 2025
  The compressor in your Samsung Air Conditioner may stop intermittently, or the fan speed of the indoor unit may decrease in COOL or DRY mode to prevent inside/outside air from freezing, depending on the inside/outside air temperature.
A
Ariel OdomAug 23, 2025
Why does my Samsung Air Conditioner compressor and indoor fan stop intermittently in HEAT mode?
- A
  Autumn FranklinAug 23, 2025
  In HEAT mode, the compressor and indoor fan may stop intermittently if the room temperature exceeds the set temperature. This is to protect the compressor from overheated air.
K
Kevin SpencerAug 26, 2025
Why do the indoor and outdoor fan stop intermittently in HEAT mode on my Samsung AQ30C2BC?
- S
  Scott MorganAug 26, 2025
  In HEAT mode, the indoor and outdoor fans may stop intermittently (for within 20% of the total heater operation) because the compressor operates in a reverse cycle to remove exterior ice.
C
Charles WatsonAug 27, 2025
What to do if only the timer LED lights up and the Samsung Air Conditioner does not operate?
- C
  cabreraaliciaAug 28, 2025
  If only the timer LED is lit and the Samsung Air Conditioner isn't operating, the timer is likely activated and the unit is in ready mode. Cancel the timer operation to make the unit operate normally.
S
Shawn WigginsAug 30, 2025
Why does the compressor stop intermittently in DRY mode on my Samsung AQ30C2BC Air Conditioner?
- J
  Jacob TaylorAug 30, 2025
  In DRY mode, the compressor operation is automatically controlled depending on the room temperature and humidity. This is why the compressor stops intermittently.
A
Alicia NealSep 1, 2025
Why is fan speed setting not allowed in AUTO or DRY mode on my Samsung AQ30C2BC Air Conditioner?
- J
  John GonzalesSep 1, 2025
  Fan speed setting is not allowed in AUTO or DRY mode because the speed of the indoor fan is set to LL in DRY mode, and fan speed (5 steps) is selected automatically in AUTO mode.
M
Mr. Jonathan DiazSep 3, 2025
What to do if the STD operation indication LED blinks on my Samsung AQ30C2BC?
- K
  Karen LewisSep 3, 2025
  If the STD operation indication LED blinks when you plug in the power plug of the indoor unit for the first time, it indicates that power is on. The LED stops blinking when you push the operation ON/OFF button on the remote control unit.
G
garciaalbertSep 6, 2025
What to do if the indoor and outdoor units of my Samsung Air Conditioner do not operate properly?
- A
  Audrey PerezSep 6, 2025
  If the indoor and outdoor units of your Samsung Air Conditioner are not operating properly, check the terminals to ensure they are correctly linked using the same number of cables.
S
Samantha LaraSep 8, 2025
Why does my Samsung AQ30C2BC Air Conditioner's timer LED light up but the unit doesn't operate?
- Y
  ywalkerSep 8, 2025
  The timer is likely activated, placing the unit in ready mode. To resolve this, cancel the timer operation. After canceling, the unit should operate normally.

Summary

1. Installation

1-1 Refrigerant Refill Procedure

Procedure for refilling refrigerant after leaks or installation.

1-2 Pump down Procedure

Procedure for recovering refrigerant when relocating or replacing evaporator.

2. Disassembly and Reassembly

Indoor Unit Disassembly

Steps for disassembling the indoor unit components like the front grille.

Outdoor Unit Disassembly

Steps for disassembling the outdoor unit components like covers and control box.

3. Troubleshooting

3-1 Items to be checked first

Initial checks for common air conditioner operational issues and symptoms.

3-2 Fault Diagnosis by Symptom

Diagnosing faults by symptom, covering various operational issues and error codes.

3-3 Replace PCB module

Procedure for replacing the main PCB module.

4. Exploded Views and Parts List

4-1 Indoor Unit

Exploded view and parts list for the indoor unit of the air conditioner.

4-2 Outdoor Unit

Exploded view and parts list for the outdoor unit of the air conditioner.

4-3 PCB Box

Exploded view and parts list for the indoor unit's PCB box.

5. Refrigerating Cycle Block Diagram

6. PCB Diagrams

6-1 Main PCB

Schematic diagram of the main PCB for the indoor unit.

7. Wiring Diagrams

7-1 Indoor Unit

Wiring diagram for the indoor unit of the air conditioner.

7-2 Outdoor Unit

Wiring diagram for the outdoor unit of the air conditioner.

This document serves as a comprehensive service manual for the Samsung ROOM AIR CONDITIONER, specifically for indoor unit model AQ30C2BC and outdoor unit model UQ30C2BC. It provides detailed instructions for installation, disassembly, reassembly, troubleshooting, and includes exploded views, parts lists, refrigerating cycle block diagrams, wiring diagrams, and schematic diagrams.

Function Description:

The Samsung ROOM AIR CONDITIONER is designed to provide cooling and heating functionalities for indoor spaces. It operates by circulating refrigerant through an indoor evaporator unit and an outdoor condenser unit, facilitating heat exchange to regulate room temperature. The system includes various components such as a compressor, fan motors for both indoor and outdoor units, a 4-way valve for switching between cooling and heating modes, and a control system with sensors and a main PCB to manage operation.

Important Technical Specifications:

Indoor Unit Model: AQ30C2BC
Outdoor Unit Model: UQ30C2BC
Refrigerant Refill Procedure:
- Standard pressure for regular, high operation mode: 4.5~5.5 kg/cm².
Input Voltage: Rating voltage ±10% range.
DC Regulator IC KA7805 (IC02):
- Input voltage: 11.5VDC-12.5VDC
- Output voltage: 4.5VDC-5.5VDC
Indoor Unit Fan Motor Supply Voltage: AC 180V (measured at PCB CN73, pin3, pin5 during fan operation).
Room Sensor Normal Register (at 25°C): 10 kΩ.
- 10°C: 17.96 kΩ
- 20°C: 12.09 kΩ
- 30°C: 8.3 kΩ
Power Relay RY71 (Compressor) / RY73 (4-way valve) / RY72 (Outdoor fan) Voltage: DC 12V.
Solid State Relay (SS71) Voltage: 12V.
Micom (IC04) Pin #43 (Heat mode): DC 4.8V.
IC06 (KID65003) Pin #16 (Heat mode): LOW (0V).
Voltage between CN71 #5 and CN78 #1 (Heat mode): Rating voltage ±10% range.
Remote Control Unit Battery Voltage: Should be greater than 2.5V.
Refrigerating Cycle STD Pressure (3-Way Valve):
- Cooling: 57-71 psi
- Heating: 270-327 psi
Refrigerating Cycle Piping Temperature (T1/T2):
- Cooling (Standard): 46-54°F
- Heating (Standard): 90-97°F (T1), 140-158°F (T2)
Use Temperature Conditions (Indoor DB/WB, Outdoor DB/WB):
- Cooling (Standard): Indoor 80/67°F, Outdoor 95/75°F
- Cooling (Max over load): Indoor 80/67°F, Outdoor 115/75°F
- Cooling (Low temp): Indoor 67/57°F, Outdoor 67/57°F
- Heating (Standard): Indoor 70/59°F, Outdoor 47/43°F
- Heating (Max over load): Indoor 80/--°F, Outdoor 75/65°F
- Heating (Low temp): Indoor 70/59°F, Outdoor 35/33°F

Usage Features:

The air conditioner offers various operational modes, including Cool, Heat, Dry, and Auto. Users can control the unit via a remote control, which allows for setting temperature, fan speed, and activating functions like the timer. The indoor unit features an LED display that blinks to indicate power status, timer activation, or specific self-diagnosis errors.

Cool Operation Mode: The compressor operates based on the room temperature relative to the set temperature.
Heat Operation Mode: The compressor and indoor/outdoor fans adjust operation to maintain the set temperature. De-ice activation can cause the compressor to continue running for up to 9 minutes after the unit is turned off.
Dry Mode: Fan speed is automatically set to LL (low) and compressor operation is controlled based on room temperature and humidity.
Auto Mode: Fan speed is automatically selected from 5 steps.
Self-Diagnosis Display: The indoor unit's display panel provides visual cues (LED blinking patterns) for various operational conditions and errors, such as:
- STD LED blinking (1Hz): Restore from power failure (initial power input).
- TIMER LED blinking (1Hz): Indoor unit Room sensor Error (open or short).
- STD and TIMER LED blinking (1Hz): Indoor unit heat exchanger temperature sensor Error (open or short).
- BIO LED blinking (1Hz): Indoor fan malfunctioning (for speed below 450rpm).
- STD, BIO and TIMER LED blinking (1Hz): EEPROM Error.
- All LED blinking (1Hz): Option Error (option wasn't setup or option data error).
Remote Control Operation: The unit responds to ON/OFF, swing button, and other commands from the remote control. A "beep" sound confirms successful command reception.

Maintenance Features:

The manual details several procedures for maintenance and repair, emphasizing safety precautions such as stopping operation and removing the power cord before any work.

Refrigerant Refill Procedure:
1. Purge air (for new installations).
2. Connect a pressure gauge to the service valve.
3. Connect the refrigerant tank.
4. Set the unit to cool operation mode.
5. Monitor pressure gauge (low pressure side) to ensure it's within 4.5~5.5 kg/cm².
6. Gradually fill with refrigerant until the rated pressure is reached.
7. Stop operation, disconnect the gauge, and close valve caps.
"Pump Down" Procedure (for evaporator replacement or unit relocation):
1. Remove caps from 2-way and 3-way valves.
2. Connect a pressure gauge to the service valve and open the 3-way valve.
3. Set the unit to cool operation mode (ensure compressor is operating).
4. Close the 2-way valve.
5. When the pressure gauge indicates "0", close the 3-way valve.
6. Stop operation.
7. Close valve caps.
Relocation of the Air Conditioner:
1. Perform the pump down procedure.
2. Remove the power cord.
3. Disconnect assembly cables from indoor and outdoor units.
4. Remove flare nuts connecting indoor unit and pipe, covering pipes to prevent foreign material entry.
5. Disconnect pipes from outdoor unit, covering valves and pipes.
6. Store connection pipes and cables carefully, avoiding bending.
7. Move indoor and outdoor units.
8. Remove and relocate the indoor unit's mounting plate.
Disassembly and Reassembly (Indoor Unit):
- Front Grille: Involves separating tape, opening the inlet grille, removing filters (including optional deodorizing and electrostatic filters), loosening fixing screws, separating the terminal cover, and carefully pulling out the upper and lower parts of the discharge.
- Ass'y Tray Drain: Requires separating the drain hose, removing the display PCB, and pulling out the tray drain.
- Electrical Parts (Main PCB): Involves disconnecting all PCB connectors (including earth wire), separating the outdoor unit connection wire from the terminal block, and pulling up the Main PCB.
- Heat Exchanger: Requires loosening fixing screws on both sides, separating holder-back body parts, and lifting the heat exchanger for separation.
- Fan Motor and Cross Fan: Involves loosening fixing screws, separating the holder motor, separating the fan motor from the right fan, loosening the fixing screw of the left fan, and separating both fans from the back body.
Disassembly and Reassembly (Outdoor Unit):
- Cover Top: Loosen screws and remove.
- Back Cabi: Loosen screws and remove.
- Control Box: Loosen screw, remove, and separate wiring.
- Cover Front: Loosen screws and remove.
Troubleshooting Procedures: Detailed flowcharts guide technicians through diagnosing issues such as "No Power," "Indoor Unit Fan Does Not Operate," "Outdoor Unit Does Not Operate," "UP/DOWN Louver Motor Does Not Operate," "No Warm Air Current (Heat Mode)," and "Impossible Operation By Remote Control Unit." These procedures involve checking voltages, component functionality (e.g., relays, sensors, micom), and connections.
PCB Module Replacement: A procedure for replacing the PCB module, including checking connections and setting up model options.
Parts Lists: Comprehensive lists for both indoor and outdoor units, including part numbers, descriptions, specifications, and quantities, facilitating easy identification and ordering of replacement parts.
Wiring and Schematic Diagrams: Provide visual representations of the electrical connections and internal circuitry, essential for understanding the system's operation and for accurate troubleshooting.