Replacing a Compressor
Prerequisites
- A compressor needs to be replaced.
- A spare compressor of the same model is available and functional.
- The compressor must be replaced with the dry filter. Replacing a Filter Dryer shows how to replace the dry filter.
- Recommended materials: Phillips screwdriver, two 45# adjustable wrenches, 45# and 50# torque wrenches, 13# and 30# solid wrenches or socket wrenches, new compressor, dryer filter, refrigerant reclaiming devices, refrigerant charging devices, R410A refrigerant
Context
Components and working principle: The scroll compressor is composed of the air intake and exhaust angle valves, oil pump, motor, and electric heating belt. Air is sucked from the outside and exhausted from the position in the center. A variable-frequency scroll compressor uses a frequency converter, and generates different air volumes as the frequency changes, thereby increasing or reducing the cooling and heating capacity. When the compressor operates at a high speed, it generates a large heating or cooling capacity, which enables the room temperature to quickly reach the preset temperature. When the room temperature decreases to a value close to the preset temperature, the compressor frequency automatically decreases to a certain level to meet the heating or cooling capacity requirements and maintain the room temperature at a stable level.
- Reclaim or dispose of the refrigerant in accordance with local laws and regulations.
- When replacing a compressor, avoid skin contact with the refrigerant or lubricant to prevent frostbite or burns.
- Do not tilt the compressor during replacement to prevent lubricant leakage.
- Install a new compressor immediately after you remove the rubber plugs of the suction inlet and exhaust outlet to prevent the moisture.
Figure 6-12 shows an angle valve.
Procedure
- Tap Shutdown on the home screen of the controller. Turn off the active power switch QF1 and standby power switch QF2 (you do not need to turn on the standby switch QF2 for the model with a single power supply), and drive switch QF3.
Exercise caution because the device is still energized after it is shut down on the controller home screen.
- Open the rear door and remove the air filter.
- Reclaim the refrigerant.
- Remove the electric heating belt.
- Remove the cover of the connection box and disconnect the compressor power cables.Figure 6-13 Removing the electric heating belt and compressor power cables
- Remove the compressor.
- Heat the air intake angle valve joints using a heat gun for 10 minutes. Secure the angle nut and pipe nut on the air intake side, as shown by (1) in Figure 6-14, using two 30# adjustable wrenches respectively. Then loosen the adjustable nut using a 36# adjustable wrench to separate the pipe from the angle valve.
After removing the valve, seal the suction vent immediately to ensure that the system is clean and moisture does not enter the pipe.
- Remove the two M8 screws below the compressor bracket, as shown by (3) in Figure 6-14, using a 13# socket wrench (or solid wrench).
Do not move the compressor by moving its air exhaust vent.
- Remove the four nut washers and spring washers that secure the compressor and the bracket using a 13# socket wrench (or solid wrench), and remove the compressor.Figure 6-15 Removing a compressor bracket
- Heat the air intake angle valve joints using a heat gun for 10 minutes. Secure the angle nut and pipe nut on the air intake side, as shown by (1) in Figure 6-14, using two 30# adjustable wrenches respectively. Then loosen the adjustable nut using a 36# adjustable wrench to separate the pipe from the angle valve.
- Secure the new compressor to the bracket again using a solid wrench.Figure 6-16 Installing a compressor bracket
- Seal the screw thread joints in the pipe using sealant.
- After the installation, check that the input power cables of the compressor are in the same phase sequence as the wiring terminals.
- Secure the compressor bracket to the cabinet interior using a 13# socket wrench, as shown by 1 in Figure 6-17.
- Apply red glue from the second to the fourth circles of the inner screw thread of the suction and discharge angle valves. Secure the angle valve nuts and pipe nuts, as shown by (2) and (3) in Figure 6-17, using two adjustable wrenches, and tighten the adjustable nuts using a torque wrench.
Tighten the air intake angle valve to a torque of 180 N m and tighten the air exhaust angle valve to a torque of 120 N m.
- Install the electric heating belt, remove the connection box cover, and reinstall the cover after the compressor cables are connected.Figure 6-18 Connecting cables to the electric heating belt and the compressor
- Vacuumize the system and precharge refrigerant, as shown in Vacuumizing and Precharging Refrigerant.
- Check that the phase sequences are correct before starting the system. Then choose to check the system pressure and temperature and ensure the refrigerant is charged with an optimal system status (see Charging the Remaining Refrigerant). Ensure that the system is running normally without alarms.
- Install the air filter and close the rear door.
- Power on the device. On the LCD home screen,
choose , and clear the compressor runtime.Figure 6-19 Performance maintenance
