Retrofit Example

Where the two major heat exchangers (cooler and condensers) are in good condition, retrofitting the compressor-motor driveline maybe a viable alternative to a complete system replacement or conversion of an existing system to an alternative refrigerant. This retrofit is available from several chiller manufacturers. And it can be used with any centrifugal machine, even those that are no longer being made - such as Worthington, Westinghouse, and Chrysler Airtemp machines.

Driveline retrofits provide a new motor-compressor that is compatible with HCFC-123 or HFC-134a. This retrofit works best with relatively inefficient systems operating with a refrigerant having a high ozone depletion potential, such as CFC-11 or CFC-12, and where the heat exchanger shells (cooler and condenser) either are or can be put in good condition.

The retrofit procedure goes something like this:

1. The system is evaluated including the compressor performance and condition evaluation (and whether it's appropriately sized),

2. Shells and piping are repaired

3. The gaskets, seals, and other components in the refrigerant cycle are replaced with materials compatible with the new refrigerant

4. The system is cleaned and flushed

5. Existing motor and compressor are removed

6. The new motor-compressor assembly, control panel, and motor starter are installed

7. The system is evacuated and charged with the new refrigerant and oil

8. The wiring and control system is replaced or adapted to operate with the new motor-compressor

9. The unit is started-up and the operators are trained.