A Screw chiller is an industrial chiller using a semi-hermetic screw type compressor. Including air cooled screw chiller and water cooled screw chiller. Screw chiller models generally range from 30HP to 300HP or even larger. Screw chiller usually use single compressor or double or four compressors. Our Screw chillers mainly use the following brands: Hanbell, Bitzer, or Refcomp.

What is scroll chiller ?

A scroll chiller is an industrial chiller using hermetic scroll type compressor. Also the sroll chillers including air cooled scroll chillers and water cooled scroll chillers. Scroll chiller models usually range from 3HP to 100HP. The Scroll types compressors brands we use are: Copeland, Danfoss, Daikin, Panasonic. Compressors qty optional.

Both screw and scroll chillers have their advantages are suitable for different applications. Here are some key differences between the two:

Design: A screw chiller uses a rotary screw compressor, while a scroll chiller uses scroll compressors. The screw compressor is typically more robust and suitable for larger capacity applications, while the scroll compressor is more compact and suitable for smaller to medium-sized applications.

Efficiency: Screw chillers generally have higher efficiency compared to scroll chillers, especially at higher loads. They can provide better part-load performance and energy savings.

Noise: Scroll chillers are known for their low noise operation, making them suitable for noise-sensitive environments. Screw chillers may produce higher noise levels, although noise reduction measures can be implemented.

Capacity: Screw chillers are available in larger capacity ranges, making them suitable for industrial applications with higher cooling demands. Scroll chillers are generally used for smaller to medium-sized applications.

Reliability: Both screw and scroll chillers are reliable, but the simplicity of scroll chiller design often results in fewer moving parts and potentially higher reliability.

So when you don’t know how to chose a right chiller for your water cooling system.It is important to consider the specific requirements of your application, such as cooling capacity, efficiency, noise level, and cost, when choosing between screw and scroll chillers. Consulting with a qualified HVAC professional can help determine the most suitable option for your specific needs. You can contact us for further information and we will offer you best solution for your industrial chiller systems. Email: oumal@oumal.com. Whatsapp: 0086 15112554736.

The rated working condition of the cooling water required by the chiller is 30~35°C. The high water temperature and poor heat dissipation will inevitably lead to high condensation pressure. This phenomenon often occurs in high temperature seasons. The reason for the high water temperature may be: cooling tower failure, such as the fan is not turned on or even reversed, and the water distributor does not turn, which means that the temperature of the cooling water is high and rises rapidly; the external temperature is high, the waterway is short, and the amount of circulating water In this case, the cooling water temperature is generally maintained at a relatively high level, which can be solved by increasing the water storage tank.

2. The cooling water flow is insufficient and cannot reach the rated water flow:

The main performance is that the pressure difference between the inlet and outlet of the unit becomes smaller (compared with the pressure difference at the beginning of the system's operation), and the temperature difference becomes larger. The cause of insufficient water flow is the lack of water or air in the system. The solution is to install an exhaust valve at a high place in the pipeline to exhaust; the pipeline filter is clogged or too fine, and the water permeability is limited. Regularly clean the filter screen; the water pump is selected to be small and does not match the system.

3. Condenser scaling or blockage:

Condensed water is generally tap water, which is easy to scale when the temperature is above 30°C, and because the cooling tower is open and directly exposed to the air, dust and foreign matter can easily enter the cooling water system, causing the condenser to be dirty and blocked, and the heat exchange area is small , the efficiency is low, and it also affects the water flow. The performance is that the water pressure difference between the inlet and outlet of the unit and the temperature difference become larger, the temperature of the upper and lower parts of the condenser is very high when touched by hand, and the copper tube of the condenser liquid outlet is hot. The unit should be backwashed regularly, and if necessary, chemical cleaning and descaling should be carried out.

4. Too much refrigerant charge:

This kind of situation generally occurs after maintenance, and the performance is that the suction and discharge pressure and the balance pressure are high, and the operating current of the compressor is also high. Under the rated working condition, the air should be released according to the suction and exhaust pressure, balance pressure and operating current until it is normal.

5. The refrigerant is mixed with air, nitrogen and other non-condensable gases:

This kind of situation usually occurs after maintenance and the vacuuming is not complete. It can only be drained, re-evacuated, and re-charged with refrigerant.

6. False alarms caused by electrical failures:

Because the high-voltage protection relay is damp, poor contact or damaged, the electronic board of the unit is damp or damaged, and the communication failure causes false alarms. For this kind of false fault, the high-voltage fault indicator light on the electronic board is often off or dimly lit, the manual reset of the high-voltage protection relay is invalid, and the operating current of the measured compressor is normal, and the suction and discharge pressure are also normal.

7. The evaporation pressure is too low:

It may be that the evaporation pressure of the water-cooled chiller is too low due to insufficient refrigerant. Common reasons: Insufficient cooling water; less cooling load; throttle orifice failure (only makes the evaporation pressure low); the heat transfer tube of the evaporator is deteriorated due to scale and other pollution (only makes the evaporation pressure too low); Insufficient (only makes the evaporating pressure too low).

8. The oil pressure difference is too low:

If the compressor oil pressure is too low, the compressor will stop running. The common reasons are: the oil filter is clogged; too much refrigerant is mixed in the lubricating oil.

9. Oil temperature is too high:

If the oil temperature of the refrigeration compressor is too high, long-term operation will reduce the quality of the refrigeration oil and even carbonize the refrigeration oil. Common causes: the cooling capacity of the oil cooler is reduced; the supply of refrigerant for cooling the oil cooler is insufficient due to the blockage of the refrigerant filter.

10. Main motor overload:

Unbalanced power supply phase voltage; large power line voltage drop;

The introduction of various industrial chillers and common fault handling are relatively complicated. Generally, specific analysis is made according to the specific problems of the situation. It is recommended to judge according to the actual situation or contact the industrial chiller manufacturer to solve the problem.

Industrial Chillers are widely used, providing cooling water systems for industrial production and helping companies improve product output and quality. Therefore, we need to understand how to use chillers simply and correctly to avoid problems during use and delay production. Let us briefly understand the use of chillers from the following aspects.

One: the protection of the chiller:

1. Check whether the voltage is normal, lack of phase,

2. Check and record the running current.

3. Measure and record whether the high and low pressure and temperature control temperature are normal.

4. Under normal conditions, the high pressure is 1.5MPa / the low pressure is 0.45MPa4 Check whether the interlocking control circuit device is loose and aging.

5. Check whether the oil level and oil temperature are normal.

6. Check the compressor for abnormal sound and abnormal vibration.

7. Refrigerant system test.

8. Overall commissioning and testing.

9. Regularly check whether the quality of the chilled water and cooling water is normal. When the water quality of the water source becomes dirty or degenerated, please replace the water source in time.

Two: The annual maintenance of the chiller is as follows:

1. Clean the condenser (every six months of cumulative operation)

2. Cleaning the cooling tower (the water-cooled chiller should be cleaned once every three months after accumulative operation)

3. Check the refrigeration oil and lubricating oil system, and replace and supplement the industrial chiller if necessary.

4. Check the circuit system of the water chiller system.

5. Compressor motor coil insulation test for industrial chillers.

6. Check whether the filter drier is normal or not, and replace it if necessary.

Three: the precise use of chillers knowledge:

7. Check the amount of refrigerant and replenish refrigerant in time.

8. Check and correct the high and low pressure switches.

9. Check and calibrate the thermostat.

10. Test run and general calibration, test whether the superheat is normal and whether there is abnormal sound of each component.

Generally, water cooling (that is, natural water and water tower cooling methods) cannot achieve high precision and high efficiency.

The purpose of temperature control, because natural water and cooling tower heat dissipation are inevitably affected by natural air temperature, the water temperature in winter is low in summer, and the water temperature is high in summer. If the air temperature is 30°C, it is almost impossible for the water temperature to reach 10°C, so it is extremely unstable to control in this way. The water chiller is completely different from the general water cooling equipment, because the chiller has a completely independent refrigeration system, which will never be affected by the temperature and the environment. The purpose of high-efficiency temperature control. The chiller is equipped with an independent water circulation system, and the water in the chiller is recycled, which can save a lot of water. Therefore, industrial production is inseparable from industrial chillers. Oumal specializes in the production of industrial chillers to help companies provide industrial chilled water system solutions. Contact us if you are looking for a solution for your industrial chilled water system.