We can see from the above schematic, a water-cooled chiller absorbs heat from the application and transfers it to the cooling (condenser) water. The warm cooling water is then pumped to the cooling tower, and the heat generated in the process is eventually released into the atmosphere. The chilled water will be pumped to the buffer tank and stored there for subsequent use.

• Consume more than 10% less energy than air-cooled chillers.
• Cheaper for the same cooling capacity.
• Have a longer lifespan.
• Relatively quiet than air-cooled chillers.
• Provide more consistent cooling performance.

Water-cooled chillers are more cost-effective than air-cooled chillers in situations where a big cooling capacity is required. (If a water-cooled chiller isn’t what you need, please refer to air-cooled chiller.)

3. How to choose the right cooling capacity for a water-cooled chiller?

One of the most frequently asked about chiller specifications is how to determine sizing/tonnage. Let’s see the below formula.

• Calculate Temperature Differential = Incoming Water Temperature (°c) – Required Chilled Water Temperature
• Calculate the water flow rate that you need per hour(m³/hour)
• Calculate tons of cooling capacity = Water Flow Rate x  Temperature Differential ÷ 0.86 ÷ 3.517
• Oversize the chiller by 20% Ideal Size in Tons = Tons x 1.2
• You have the ideal size for your needs. 

For example, what size of chiller is required to cool 5m³ water from 25°c to 15 °c in 1 hour?

• Temperature Differential = 25°c-15°c=10°c
• Water Flow Rate = 5 m³/hour
• Ton Capacity = 5 x 10 ÷ 0.86 ÷ 3.517 = 16.53 Tons
• Oversize the chiller = 16.53 x 1.2 = 19.84 Tons
• A 19.84 Tons chiller is required.

You can also use our chiller calculator to do the math work.

If your target temperature is lower than 5°c, please contact us for further assistance.

4. What else should I look for in choosing the right chiller?

Other important chiller specifications include the voltage required for operation, the associated pump horsepower and flow rate (contact us for custom selection), the water connection size, and the evaporator type.

4.1 Power

Different countries and regions have different standards for industrial electricity, the common power supplies are 208-230V, 380-420V,440-480V,50Hz or 60Hz, 3phase.

4.2 Water Pump

When you decide the capacity/tonnage of the chiller, we will recommend you the suitable horsepower of the pump. Or you can check our product manual.

4.3 Connection Size

This usually depends on the water flow rate, the higher the bigger. If you want your new chiller to match your old pipes, we can also customize accordingly. For more detailed specifications, please refer to our product page or check our product manual.

4.4 Refrigerant

R22, R410A, R407C, R404A, R134A are optional choices.

R22: good cooling effect, but R22 is considered a powerful greenhouse gas, so it’s forbidden in most countries.

R410A: eco-friendly, R-410A has replaced R-22 as the preferred refrigerant for use in residential and commercial air conditioners in Japan, Europe, and the United States. R-410A operates at higher pressures than other refrigerants.

R407C: a good replacement for R22, good cooling effect.

R404A: suitable for application that requires low temperature(below -30°c).

R134A: a non-flammable gas used primarily as a “high-temperature” refrigerant, suitable for air-cooled chiller working at a high ambient temperature.

4.5 Evaporator Choose

Air chillers have two general types of evaporators.

• Shell and tube type evaporator, which requires an additional water buffer tank to use(not necessary but highly recommended).

• Coil and tank evaporator, which has a built-in water storage tank for more convenient use. So there’s no need for extra buffer tanks.

These two evaporator coils can be made of 2 materials, copper or stainless steel tube.

What is the difference between these 2 options?

1. Copper tube: better heat transfer efficiency.
2. Stainless steel tube (304 or 316): also known as food-grade material, it is suitable for the food/beverage industry and can avoid water contamination.

5. Summary

Each unit includes hermetic scroll compressor(or semi-hermetic screw compress), water-cooled condenser, fully charged refrigerant of R22(R410A, R404A, R407C, R134A optional), shell& tube type evaporator(or tank& coil type evaporator), and a weather-resistant control center, all mounted on a beautiful and solid steel box(or rugged steel base).

At SCYChiller, we design and manufacture the best chiller units to help you overcome your most challenging problems, and SCYChiller will provide you with unconditional, expert advice to help you turn your challenges into real solutions.