They are all called chillers, but water chilling systems for a plastics plant, a pharmaceutical plant and a food plant are designed around three different problems. Choosing the wrong configuration does not stop the system — it simply makes operating costs higher than they need to be, or leaves the production process short of requirement.
What they share: a chiller serves the process, not the people
A chiller in a factory differs from one in a building because it is tied to the production line. If the chiller stops, the line stops with it. That creates three common requirements for every sector:
- Reliability matters more than absolute efficiency — this usually calls for a multi-unit configuration rather than one large unit
- Stable leaving water temperature, because fluctuation directly affects product quality
- Continuous operation, so maintenance must be possible without shutting the whole system down
Plastics plants: the cycle and fluctuating load problem
A chiller for injection moulding cools the moulds. What is distinctive here is that the load varies with the moulding cycle, and the mould cooling time determines the output of the whole moulding machine.
Design consequences:
- A thermal storage tank large enough to absorb load swings is needed, to stop the compressor cycling constantly
- A stable leaving water temperature — fluctuation changes mould cooling time, which makes product dimensions inconsistent
- If the water temperature is lowered too far to shorten the cycle, the risk of condensation on the moulds must be taken into account
A common mistake: setting the leaving water temperature lower than the process needs, on the assumption that colder is faster. Every extra degree lower reduces efficiency and increases electricity consumption.
Pharmaceutical plants: the stability and documentation problem
In pharmaceutical manufacturing, the chiller usually supplies cooling to the cleanroom air conditioning system and to certain temperature-controlled process steps. The requirement shifts from efficiency to demonstrability:
- Temperature stability within a narrow band, continuously recorded
- A redundant configuration — one unit failing must not interrupt cleanroom conditions
- Complete equipment documentation and sensor calibration records for validation
- A control system with alarms and data logging, usually integrated with SCADA
In this sector, a high-efficiency chiller system lacking documentation and redundancy will not pass assessment — however well it runs.
Food plants: the hygiene and low temperature problem
A chiller in a food plant supplies cooling to the processing area, to product cooling processes, and sometimes to the store's refrigeration system as well. Two main characteristics:
- The temperature range is usually lower than comfort cooling requires, and in many cases glycol must be used instead of water so the coolant does not freeze
- Hygiene requirements for heat exchangers in indirect contact with the product, and equipment layouts that allow periodic cleaning
When using glycol, watch the concentration: mixing it stronger than necessary raises viscosity, reduces heat transfer and makes the pumps consume more electricity. The concentration should be just enough for the actual operating temperature.
Quick comparison across the three sectors
| Criteria | Plastic | Pharmaceutical | Food |
| Top priority | Cycle stability | Stability and documentation | Hygiene and low temperature range |
| Load characteristic | Fluctuates with the moulding cycle | Relatively steady | Follows the production shift |
| Coolant | Water | Water | Water or glycol |
| Redundancy | According to criticality | Almost mandatory | According to criticality |
| Item most often overlooked | Thermal storage tanks | Documentation and calibration | Layout for cleaning |
Three questions to answer before choosing a chiller
- What leaving water temperature does the process actually need? Not the lowest achievable, but the level the process requires. Every extra degree lower reduces efficiency.
- How does the load change during a production shift? A strongly fluctuating load needs a thermal storage tank or a multi-unit configuration, not one large unit.
- How much does a system shutdown cost? The answer determines how much to invest in redundancy — and this is the item most often cut, right up until the first incident.
Tan Long advises on and installs chiller systems around each plant's specific problem, including the pipework, pumps and control panel.
Frequently asked questions about choosing a chiller by sector
How does a chiller for a factory differ from one for a building?
A factory chiller is tied to the production line — if it stops, the line stops with it. Reliability and leaving water temperature stability therefore take priority over absolute efficiency, and a multi-unit configuration is usually used rather than one large unit.
Why does a plastics plant need a thermal storage tank?
Because the load varies with the moulding cycle. Without a thermal storage tank the compressor cycles constantly and wears, and a fluctuating leaving water temperature changes mould cooling time, making product dimensions inconsistent.
What does a chiller for a pharmaceutical plant need in particular?
Stability within a narrow band with continuous recording, a redundant configuration so one unit failing does not interrupt cleanroom conditions, and complete equipment documentation and sensor calibration records for validation.
When should glycol be used instead of water?
When the coolant temperature needs to go below the freezing point of water. Note that the concentration should be just enough for the actual operating temperature — stronger than necessary raises viscosity, reduces heat transfer and wastes pump energy.
Should the leaving water temperature be set lower than needed?
No. Every extra degree lower reduces efficiency and increases electricity consumption. Determine the temperature the production process genuinely requires rather than setting the lowest achievable level.
Related pages
- Water-cooled or air-cooled chillers
- Saving electricity on chiller systems
- What is a chiller? Construction and operating principle
- Chiller maintenance: procedure and warning signs
- Water Chiller
- Glycol water chilling systems
Is your business in need of a survey, upgrade, or new design for your industrial refrigeration system?
With over 18 years of practical experience leading more than 29 major national projects, Tan Long's team of HVAC engineers is committed to providing accurate thermal load calculations, optimizing the COP efficiency coefficient, switching between natural refrigerants NH3/CO2, and saving 20–30% in operating electricity costs.
Engineer Nguyen Toan Thinh (Technical Director)
With over 18 years of practical experience in directing, consulting, designing, and constructing heavy industrial refrigeration systems, ASRS automated warehouses, and IQF freezing systems across more than 29 major national projects.
