What is the cooling process of the chiller?

The evaporator, compressor, condenser and contraction installation of the chiller have experienced a thermodynamic process in the cooling process. The following four stages summarize the working mode of the chiller:

Stage 1 - first, the evaporator of the chiller acts as a heat exchanger to collect process heat and transfer it to the cold liquid refrigerant in the chiller. Then, the heat of the process boils the refrigerant and converts the refrigerant from low-pressure liquid to low-pressure gas. At the same time, the temperature of the process coolant decreases.

Stage 2 - next, the low-pressure gas enters the compressor, and its main task is to increase the pressure of the outgoing refrigerant steam to a high enough temperature to release heat in the condenser.

Stage 3 - in the condenser, the refrigerant vapor returns to the liquid. The heat taken away by ambient air or condensate during the conversion from steam to liquid depends on whether you use an air-cooled or water-cooled chiller.

Stage 4 - the last stage of the cooling process involves the liquid refrigerant entering the compression valve, stopping metering and repeating the cooling cycle again before entering the evaporator.

Check whether the following contents are correct before the operation of the chiller:

1. Please refer to the nameplate for whether the power supply voltage and phase number meet the model and specification. (Note: above 3 HP freezers).

The power supply adopts the three-phase five wire system with the voltage of 380 ~ 415 V / 50 Hz. The power supply phase line is divided into R, s, t, neutral line (zero line) n, and the two-color line represented by e for the grounding wire. The phase staggering protector is installed. When the light is not on or the red light appears at the second startup, the fault code and alarm number are displayed, and any two phase lines can be connected and closed. " The cold storage below 3HP adopts single-phase power supply with voltage of 220 ~ 240 V / 50 Hz. The phase line of the power supply is l, the neutral line is n and the ground line is e.

2. Whether the chilled water pipe and cooling water pipe are connected with the pipe and keep the valve open (refer to the installation drawing).

3. Fill the refrigerator with water or other refrigeration medium before starting the pump (Note: Please match the refrigerant as required).

4. Please pay attention to the running direction of the cooling water pump and whether the water tower fan is reversed (if the water pump is three-phase, any two phases on the power supply phase line must be replaced before turning off the switch).

Work flow of chiller inspection:

1. Check whether the pump steering is correct.

2. The compressor is separated from the motor to determine whether the rotation direction of the motor is correct.

3. When the compressor oil is added to the chiller, the oil should be kept at 1 / 2 / 3 / 4 of the apparent oil mirror, and should not be filled at the place where the compressor oil is added to the chiller.

4. Check whether the differential pressure relay on the suction side and filter, the pressure relay on the exhaust side, the pressure of oil pressure and cooling water, and the operation of oil pressure relay and oil pressure relay are sensitive.

5. Install the coupling and correct it.

6. Inject refrigerant (usually R22) into the system as required.

When using the chiller, do not forget these preparations to avoid some problems in the formal operation of the chiller, which will be difficult to solve.