How to protect refrigeration unit when the ambient temperature is too high
Excessive ambient temperature may cause the following problems in the unit and cause the unit to alarm for high pressure.
When the ambient temperature is high, the poor heat dissipation of the condenser may cause the high pressure alarm of the unit.
(1) Air-cooled condenser
A heat exchanger that converts gas or vapor into liquid.
It is recommended that the ambient temperature of this heat exchanger should not exceed 40°C, otherwise it will be prone to high-voltage alarms due to poor fan heat exchange due to high ambient temperature.
In addition, the dust accumulated on the fins of the air-cooled condenser will also lead to poor heat exchange effect of the fan. The side ends of the fan fins are air inlets, which are easy to accumulate dust, and the fan fins need to be cleaned regularly.
Cleaning method: Use a soft brush or a vacuum cleaner with a brush to clean the fins from top to bottom. Note: Do not brush left or right, do not use excessive force, and do not use hard objects to clean, so as not to bend or damage the fins.
At the same time, Arkref recommends that you place the device in a covered and sheltered ventilated place, which is conducive to heat dissipation of the device and reduces dust accumulation.
(2) Water-cooled condenser
Water is used as the cooling medium to condense high-temperature and high-pressure gaseous refrigerant.
The inlet water temperature of the water-cooled condenser is 25°C~35°C, and the inlet water pressure is about 5bar (0.5MPAa).
In a high-temperature environment, if the equipment and water supply pipes are exposed to the sun, the temperature will rise, resulting in a higher temperature of the internal cooling water, which will affect the operation of the equipment. Therefore, before starting up and running, the water in the water supply pipeline can be pre-circulated and cooled.
During the operation of the water-cooled condenser, the cooling water supply is less or the cooling water pump is damaged, resulting in no circulation of the cooling water, which may also trigger the high-pressure alarm of the equipment.
At the same time, the cooling water is easy to generate scale in the pipeline, which affects the heat exchange effect. Especially in areas with hard water quality, Arkref recommends that you increase the frequency of cleaning, which can be done every three months. In areas with soft water quality, you only need to clean it twice a year.
(3) Evaporative cooling condenser
It is a kind of equipment that absorbs the heat of the high-temperature gaseous refrigerant in the coil when the spray water outside the coil is partially evaporated, so that the refrigerant in the tube is gradually cooled from gaseous state to liquid state.
Similar to a water-cooled condenser, in a high-temperature environment, the temperature of the equipment and water supply pipes will rise after being irradiated by the sun, resulting in a higher temperature of the internal cooling water, which will affect the operation of the equipment. Therefore, before starting up and running, the water in the water supply pipeline can be pre-circulated and cooled.
The plant reproduction of water algae is easy to block the evaporative cooling condenser. Harder water contains calcium and magnesium ions, which are more likely to be precipitated when the temperature rises and heated, and bonded to the metal surface to form scales that affect heat transfer.
Therefore, regularly change the water for the evaporative condenser or clean the sink, water pipes, filters, nozzles and other parts to avoid affecting the heat exchange effect of the equipment due to scale.
2. Refrigeration oil
(1) When the equipment is running, the refrigeration oil plays a role in lubricating and cooling the compressor. When the refrigeration oil inside the equipment expires or deteriorates, it is easy to cause insufficient lubrication inside the compressor, resulting in high pressure and high temperature of the equipment.
(2) Affected by the high temperature environment, too high temperature of the refrigeration oil will easily reduce the viscosity of the refrigeration oil when the equipment is running, and oil leakage will occur, which will affect the heat exchange effect of the equipment and lead to high pressure of the equipment.
(3) Adding too much refrigerating oil will also cause excess refrigerating oil to stay inside the condenser and evaporator, affecting the heat exchange of the equipment and resulting in high pressure of the equipment, and a certain amount of refrigerating oil needs to be discharged.
(4) Too little refrigeration oil will also lead to insufficient internal lubrication of the compressor during operation. Especially when the ambient temperature is too high, it is more likely to cause a high-pressure alarm, and the refrigeration oil should be replenished in time.
Excessive refrigerant charging will also cause the pressure in the equipment to rise, especially in the case of high ambient temperature, which will cause the equipment to be overpressured during operation, and part of the refrigerant should be discharged.