A refrigeration unit that cools water or glycol and circulates it to take heat out of a process or machine.
01 / Definition
What a Industrial Chiller is
An industrial chiller moves heat out of your process water and dumps it somewhere else. It runs the vapour-compression cycle: the compressor raises refrigerant pressure and temperature, the condenser rejects that heat to air or to cooling water, an expansion device drops the pressure sharply, and the now-cold refrigerant absorbs heat from your process water in the evaporator before returning to the compressor.
The number that tells you how well it is working is the approach — the gap between the chilled water temperature and the refrigerant's evaporating temperature. A widening approach means heat is no longer crossing the exchanger properly, usually because of fouling or low refrigerant charge, and it shows up long before the chiller actually fails to hold setpoint.
Also called
02 / Anatomy
The parts that matter
The components a technician reaches for when this machine stops working.
Compressor
Scroll, screw or reciprocating. Raises refrigerant pressure and is the component most damaged by poor maintenance elsewhere.
Condenser
Rejects heat to air or water. Fouling here raises head pressure and is the most common cause of high-pressure trips.
Expansion valve
Drops refrigerant pressure and meters flow into the evaporator. A hunting valve causes unstable chilled water temperature.
Evaporator
Where process water gives up its heat. Scale or low flow here causes freeze trips.
Chilled water pump and tank
Circulate water to the process and buffer the load so the compressor is not short cycling.
Controller and safeties
Hold setpoint and protect against high head pressure, low suction, freeze and flow loss.
03 / Applications
Where it is used
Cooling moulds, spindles, welding equipment, hydraulic oil and reactor jackets.
04 / Failure modes
How it fails
What actually goes wrong on Indian shop floors, and what each fault looks like to the operator.
FM_01
High pressure trips
Condenser fouled with dust, condenser fan failed, or cooling tower water flow lost. Summer ambient makes a marginal condenser trip daily.
FM_02
Not holding setpoint
Low refrigerant charge, fouled evaporator, or a process load that has grown beyond the chiller's capacity.
FM_03
Freeze trips
Low chilled water flow through the evaporator — a blocked strainer, a closed valve or a failing pump.
FM_04
Short cycling
Too little water volume in the loop, so the compressor satisfies setpoint instantly and restarts. Hard on compressor motors.
FM_05
Refrigerant leaks
At flare joints, valve stems and vibrating pipework. Performance degrades gradually rather than failing outright.
05 / Onsite
What our technician checks
A methodical path to root cause, not a scattergun of part swaps.
- 01Record chilled water in and out temperatures and the approach, then compare against commissioning figures
- 02Inspect condenser coils or tubes for dust and scale, and confirm every condenser fan runs
- 03Check chilled water flow and strainer condition — most freeze trips are flow problems, not refrigerant problems
- 04Read suction and discharge pressures and convert to saturated temperatures to judge charge and heat transfer
- 05Check loop water volume against compressor cycling, and look at run-time logs for short cycling
- 06Leak-test joints and valve stems if charge has been topped up more than once
06 / Get it fixed
Related services
The MachineryFix services that cover this equipment.
07 / Questions
Frequently asked questions
Why does my chiller trip on high pressure in summer?+
The condenser cannot reject heat fast enough. Dust-blocked coils, a failed fan or lost cooling tower flow all raise head pressure, and higher ambient pushes a marginal condenser over the trip point. Clean the coils and verify every fan before adding refrigerant.
What does the approach temperature tell me?+
It is the gap between chilled water temperature and the refrigerant's evaporating temperature, and it measures how well heat is crossing the exchanger. A widening approach signals fouling or low charge well before the chiller stops holding setpoint.
Why does the chiller keep freeze-tripping?+
Almost always low water flow through the evaporator rather than a refrigerant fault — a blocked strainer, a partly closed valve, or a tiring pump. With too little flow the water in the tubes gets too cold and the safety does its job.
Can I just top up refrigerant when cooling drops?+
A chiller is a sealed system; if charge is low, refrigerant has escaped and will escape again. Topping up buys weeks and vents refrigerant to atmosphere. Find and repair the leak, then charge by weight to the nameplate figure.
Written & reviewed by MachineryFix — last reviewed — questions? Call +91 70133 33007