Operation method of air discharge in refrigeration system of industrial chiller
One, the operation steps of the chiller of the Freon system
1. Close the outlet valve of the accumulator or the outlet valve of the condenser
2. Start the compressor and collect the refrigerant in the low pressure section into the condenser or accumulator
3. After the low pressure system pressure drops to a stable vacuum state, stop
4. Loosen the bypass hole screw plug of the exhaust shut-off valve, and turn it clockwise (turn the exhaust valve stem about half a turn to make the valve a three-way shape, allowing high-pressure gas to escape from the bypass hole. Block the exhaust airflow with the palm of your hand. When you feel cold air and oil stains on your hands, it means that the air has been basically exhausted. The screw plug should be tightened, the exhaust valve stem should be reversed, and the bypass hole should be closed.
5. Matters needing attention:
①The venting time should not be too long each time, and it can be performed continuously 2 to 3 times to avoid wasting refrigerant.
②If a backup stop valve is installed on the top of the condenser or accumulator, the air can be discharged directly from the valve.
II. Operation steps of the chiller for ammonia refrigeration system
1. When using an air separator to discharge air, place the return valve of the air separator in a normally open state to reduce the pressure of the air separator to the suction pressure. All other valves should be closed.
2. Properly open the mixed gas inlet valve to allow the mixed gas in the chiller refrigeration system to enter the air separator.
3. Slightly open the liquid supply valve (the degree of opening should depend on the frosting condition of the return air pipe, generally controlled at about lm to frost the return air pipe) to throttle the ammonia into the air separator and absorb heat. Cool down the mixed gas.
4. Connect the rubber hose used for the air release valve interface and insert one end into the water in the water container. When the ammonia in the mixed gas is cooled into ammonia liquid, frost will form on the bottom of the air separator. At this time, the air valve can be slightly opened to discharge the air through the water container. If the bubbles are round in the process of rising in the water, and there is no volume change, the water is not turbid and the temperature does not rise, then air is released. At this time, the opening of the air release valve should be adjusted properly. If the volume of the bubbles gradually shrinks or even disappears during the ascending process, the water becomes milky white and turbid, and the water temperature rises, it indicates that the released gas contains more ammonia, indicating that the air has been exhausted and the air release operation should be stopped.
5. The ammonia in the mixed gas is gradually condensed into ammonia liquid and accumulated at the bottom. The liquid level height can be seen from the frosting of the shell. When the liquid level reaches 12, close the liquid supply throttle valve, close the liquid supply throttle valve, and open the liquid return throttle valve. The bottom ammonia liquid is returned to the air separator to cool the mixed gas. When the bottom frost layer is about to melt (indicating that the condensed ammonia is about to be drained), close the liquid return throttle and open the liquid supply throttle.
6. When stopping the air release, first close the air release valve to prevent ammonia gas from leaking out, and then close the liquid supply throttle valve and the mixed gas inlet valve. In order to prevent the pressure in the air release device from increasing, the return valve should not be closed.
