Industrial Chiller Not Cooling? Your Essential 10-Point Diagnostic Checklist

Phase 1: The Water and Heat Rejection Loop

These are the most common and often easiest problems to fix.

1. Is the Water Flow Strong and Steady?

• The Problem: Low or restricted flow stops heat exchange, often triggering low-flow alarms.

• What to Check:
  • Filters: Is the water strainer clogged with debris? Clean it immediately.
  • Valves: Are all chilled water valves fully open?
  • Pumps: Is the pump running normally without unusual noise?

2.How Does the Condenser Look?

• The Problem: The chiller can’t cool if it can’t dump the heat, leading to high head pressure.
• What to Check:
  • Air-Cooled: Are the condenser fins blocked with dirt or dust? Clean them. Are the fans operating correctly?
  • Water-Cooled: Check the cooling tower water temperature. Are the chiller tubes scaled or fouled (requires professional cleaning)?

3. Is the Glycol Concentration Correct?

• The Problem: Incorrect glycol mix (antifreeze) reduces heat transfer efficiency and risks evaporator freezing.
• What to Check: Use a refractometer to verify the freeze point is adequate for your operation.

Phase 2: The Refrigeration Cycle

These issues are complex and typically require a professional focused on industrial chiller system repair in Dubai.

4. Check for Refrigerant Leaks

• The Problem: Low refrigerant charge means insufficient mass flow to carry the heat away, leading to low cooling capacity.
• What to Check: Look for unusually low suction pressure or frost on the lines. Do not add refrigerant yourself. Reliable industrial chiller system repair in Dubai requires leak detection and repair first.

5. How’s the Compressor Sounding?

• The Problem: If the heart of the system is failing, it won’t compress vapor effectively.
• What to Check: Is it running but short-cycling? Is it making abnormal noise or vibrating excessively? Worn internal components reduce efficiency.

6. Are There Non-Condensables in the System?

• The Problem: Air and moisture contamination drastically increase head pressure and compromise cooling capacity.
• What to Check: If the condenser pressure is unusually high despite clean coils, this is the likely cause.

7. Is the Expansion Valve Operating? (TXV)

• The Problem: The valve controls refrigerant flow. If it’s stuck open or closed, the evaporator is either flooded or starved, hurting cooling.
• What to Check: Check superheat readings across the evaporator.

Phase 3: Electrical, Controls, and Environment

These are often control or environmental issues.

8. Check Electrical Safeties and Fault Codes

• The Problem: The chiller likely shut down to protect itself.
• What to Check: Look for tripped circuit breakers. Check the control panel immediately—the fault code is your best clue (e.g., “Low Flow Trip”).

9. Confirm Control Setpoints

• The Problem: Sometimes the setpoint was changed, or a faulty sensor is misreporting the temperature.
• What to Check: Verify the correct chilled water setpoint and compare the sensor reading against an external thermometer.

10. Assess Ambient Conditions and Heat Load

• The Problem: The chiller can be overwhelmed by external heat or excess operational load.
• What to Check: Is the ambient temperature around air-cooled units too high? Is the current process load exceeding the chiller’s tonnage capacity?