Guide for diagnosing insufficient capacity of industrial cooling systems

1. Problem description and scope

This guide is intended for diagnosing and solving problems related to insufficient capacity of industrial cooling systems. Changes in temperature, loss of cold, instability of the temperature regime, or lack of effective cooling may indicate incorrect design power, uneven flow, scale accumulation, or incorrect refrigerant volume. The problem can be critical, especially in manufacturing, where loss of cooling can cause production shutdowns or equipment damage.

2. Safety precautions

Use personal protective equipment (PPE): gloves, goggles, means of protection against harmful substances, means of protection against electric shock.
Perform the lockout/mark process: before diagnosis, lock the power supply and install signatures to avoid unforeseen cases.
Carefully check for hidden energy: Before turning off the power, check for hidden energy in the system.</n

3. Necessary diagnostic tools

4. The first review checklist

5. Systematic diagnostic flow

1. Symptom: Increased temperature in the cooling system
   1. Check: Measure the temperature at different points in the system
      1. Result: The temperature is higher than the permissible value (for example, 45°C)
         1. Diagnosis: Insufficient coolant flow or scale accumulation
            1. Diagnostic check: Measure the refrigerant flow rate
               1. Answer: The flow rate is lower than permissible (e.g. 0.5 m/s)
                  1. Reasons:
                     1. Insufficient calculated refrigerant volume - check the power calculation
                     2. Irregular flow - check filters and valves
                     3. Scale build-up - check the thermograph

6. Matrix come-reasons

7. Analysis of the main reasons

7.1 Insufficient calculated volume of refrigerant

Insufficient cooling volume may occur due to incorrect power calculations or changes in external conditions. This leads to insufficient cooling. To check, use system power calculations, taking into account heat loads. If the power is lower than required, recalculate.

7.2 Uneven flow

Uneven flow can be caused by missing filters, clogged valves, or incorrect settings. Use a tachograph or flow analyzer to detect irregular flows. An increased flow rate may indicate an increased refrigerant volume or incorrect settings.

7.3 Scale accumulation

The accumulation of scale in the cooling system leads to a decrease in the efficiency of heat exchange. Use a thermograph to detect uneven temperature distribution. If irregularity is found, perform system cleaning.

8. Step-by-step solution procedures

8.1 Insufficient calculated volume of refrigerant

1. Perform a recalculation of the system power, taking into account the thermal loads.
2. Determine the required volume of refrigerant.
3. Fill the system according to the set parameters.
4. Check pressure and temperature after filling.

8.2 Uneven flow

1. Check filters and valves for contamination.
2. Clean the filters or replace them if necessary.
3. Check valve settings.
4. After the fix, check the flow rate.

8.3 Scale accumulation

1. Use a thermograph to detect unevenness.
2. Run the cooling system for cleaning.
3. Check for scale.
4. Clean the system or replace the pistons if necessary.

9. Preventive measures

10. Relevant parts and components

Learn more about the relevant parts and components in the e-catalogue UNITEC-D.

11. List of references

• DSTU 4178-2007 – Requirements for cooling systems
• EN 12952-7 – Cooling and ventilation systems
• ISO 5149:2019 – Calculation of the capacity of cooling systems
• UNITEC-D Technical manuals