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PermaFrost Case Study: Refrigerator System- November 2002

Evaluation of PermaFrost's Effects on an R22 Refrigeration System at SA Cold Stores
John Swire & Sons PTY LTD
Prepared by Andrew Pang - November 2002

NOTE: Tables and appendices referred to in this summary are available in this PDF file

INTRODUCTION
The aim of this report is to examine the effects of a product known as PermaFrost upon the refrigeration system of the cool room
at Galipo Foods. The refrigeration system utilized a Bitzer reciprocating air-cooled condensing unit, 4FC-52Y running on R-404A
refrigerant.

The aim of the report was to examine the effects of a product known as PermaFrost upon the R-22 refrigeration system at
S A Coldstore, Adelaide.

system. As each molecule attaches itself to metal surfaces within the system, it displaces dirt, carbon deposits, and lubricating
system. As each molecule attaches itself to metal surfaces within the system, it displaces dirt, carbon deposits, and lubricating
oils, eventually forming a thin layer. As a result, the system can move more heat for the same amount of compressor action.
Energy demand and consumption can be reduced."
Energy demand and consumption can be reduced."

METHODOLOGY
The testing procedure included an analysis of the refrigeration system on two occasions:

Before the addition of PermaFrost,
After the addition of the PermaFrost.

To measure the performance of the refrigeration system, an "ETM" refrigeration system analyser was used to datalog the
operating conditions of the systems during testing. For each test, the analyser collected the data on the following operating
conditions over a one hour period at five seconds interval:

Power input
Cooling capacity
Coefficient of performance (COP)
Suction superheat
Liquid subcooling
Compressor discharge temperature
Evaporating temperature & pressure
Condensing temperature & pressure

TESTING
The R22 refrigeration system was first tested on August 26, 2002 before the product, PermaFrost was introduced into the
system and then on September 21, 2002 after the treatment.

RESULTS OF TESTING
Detailed results of the operating conditions are provided in the following charts, all found in Appendix A (of full report):

1. Pre-treatment Test (August 26, 2002)

Cooling Capacity & Power Input
Coefficient of Performance & Liquid Subcooling
Discharge, Evaporating & Condensing Temperatures & Superheat
Condensing & Evaporating Pressures

2. Post-treatment Test (September 16, 2002)

Cooling Capacity & Power Input
Coefficient of Performance & Liquid Subcooling
Discharge, Evaporating & Condensing Temperatures & Superheat
Condensing & Evaporating Pressures

OBSERVATIONS
A comparison of the mean operating conditions for each of the tests are summarised in table below:

Test Results : Operating Mean Values
                                     Pre-treatment                         Post-treatment                         % change
Cooling Capacity (kW)                                   662.16                                     766.25                                   15.72
Power Input (kW)                                           166.90                                     178.72                                     7.08
Coefficient of Performance, COP                      3.97                                         4.27                                     7.56
Discharge Temperature (°C)                           66.00                                       64.03                                   -2.98
Evaporating Temperature (°C)                       -33.70                                     -28.74                                  -14.72
Condensing Temperature (°C)                        26.85                                       27.44                                     2.20
Liquid Subcooling (K)                                        3.90                                         3.42                                  -12.31
Suction Superheat (K)                                     21.35                                       19.35                                    -9.37
Condenser Cooling Water Inlet Temp (°C)      23.64                                       23.69                                     0.21
Condensing Pressure (kPa)                          996                                         1015                                         1.91
Evaporating Pressure (kPa)                            40                                             75                                       87.50

From this table, a number of observations can be made about the effects of PermaFrost on the R22 system:

Cooling capacity increased significantly by 16 % in the post-treatment test. This indicates a significant improvement in
heat transfer in the evaporators if the heat load in the store were similar during both tests.
Power input increased marginally by 7% in the post-treatment test.
The COP (a ratio of the cooling capacity and power input) increased by 8% in the post-treatment test. This indicates an
improvement in the overall system performance.
Liquid subcooling decreased by 12% in the post-treatment test.
The compressor discharge temperature was reduced by 3% in the post-treatment test. This may indicate a marginal
improvement in the lubricity of the refrigerant oil in the compressor.
The evaporating temperature and pressure increased significantly by 15% and 88%. These may indicate an increase in
the heat load in the cold store in the post test.
There were insignificant changes in the condensing temperature and pressure in the post-treatment.

CONCLUSION
The tests carried out on the R22 Refrigeration System, indicated an improvement in performance of 8% after treatment with
PermaFrost.

NOTE: The following is the executive summary of a 6-page report avail-able at SA Cold Stores R22 Refrigeration System Test:
November 2002. Tables and appendices referred to in this summary are available in this PDF file