Regency TAFE, SA. An evaluation of the effects of PermaFrost treatment on a Fujitsu Heat Pump. July Prepared by

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2 Regency TAFE, SA An evaluation of the effects of PermaFrost treatment on a Fujitsu Heat Pump July 2008 Prepared by Andrew Pang Andrew Pang & Associates Pty Ltd Phone: Facsimile: bnpang@aapt.net.au for Enrico Sgarbi enacon Holdings Pty Ltd Lobethal, SA

3 INTRODUCTION The aim of this report is to examine the effects of PermaFrost upon the refrigeration system of a two year old Fujitsu heat pump, Model AOT12LSAC. This unit is an inverter type that uses refrigerant R-410A. METHODOLOGY The testing was conducted in a laboratory at Regency TAFE, SA under control conditions. The indoor unit was placed in a room with two operating electric heaters to maintain a constant room temperature. The total heating load of the heaters was 2.25 kw. The condensing unit was placed in another room with an operating air conditioning unit to maintain a constant ambient temperature. The testing procedure included an analysis of the refrigeration system on two occasions: 1) Before the addition of PermaFrost, and 2) After addition of the product. To measure the performance of the refrigeration system, an ETM refrigeration system analyzer was used to data log the operating conditions of the systems during testing. For each test, the analyser collected the data on the following operating conditions over a 10 hour period at one minute interval for the same time period of the day: Power input Cooling capacity Coefficient of Performance, COP Compressor discharge temperature Evaporating temperature and pressure Condensing temperature and pressure Room temperature Ambient temperature TESTING The refrigeration system of the Fujitsu heat pump was first tested on July 3, 2008 before PermaFrost was introduced into the system and then on July 4, 2008 after the treatment. The two yardsticks for comparing the performance of the refrigeration system for the two tests are the ambient temperature and room temperature. The variation in the mean ambient temperature between the pre-test and the post-test was 0.10 %. The variation in the mean room temperature between the pre-test and the post-test was 1.14 %. These variations can be considered as insignificant and, hence, the ambient temperature and room temperature can be assumed to be constant for both tests.

4 The mean power consumption for the period of the pre-test was 6.2 kwh. The mean power consumption for the period of the post-test was 5.6 kwh. RESULTS OF TESTING Detailed results of the operating conditions are provided in the following charts, all found in Appendix A: 1. Pre-treatment Test (July 3, 2008) Chart 1A: Cooling Capacity, Power Input & Coefficient of Performance Chart 2A: Ambient, Room and Evaporating Temperatures Chart 3A: Condensing and Compressor Discharge Temperatures Chart 4A: Evaporator & Condenser Pressures 2. Post-treatment Test (July 4, 2008) Chart 1B: Cooling Capacity, Power Input & Coefficient of Performance Chart 2B: Ambient, Room and Evaporating Temperatures Chart 3B: Condensing and Compressor Discharge Temperatures Chart 4B: Evaporator & Condenser 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) Power Input (kw) Coefficient of Performance, COP Percentage Improvement Discharge Temperature ( C) Evaporating Temperature ( C) Condensing Temperature ( C) Condensing Pressure (Bar Gauge) Evaporating Pressure (Bar Gauge) Room Temperature ( C) Ambient Temperature ( C) From this table, a number of observations can be made about the effects of PermaFrost on the Fujitsu heat pump:

5 Cooling capacity increased by % in the post-treatment test. This indicates a significant improvement in heat transfer in the evaporator. Power input decreased by 9.68% in the post-treatment test. This indicates a significant decrease in power consumption by the compressor. The COP (a ratio of the cooling capacity and power input) increased by 31.05% in the post-treatment test. This indicates a significant improvement in the overall system performance. The compressor discharge temperature decreased by 1.94%. The increase in evaporating temperature and pressure further indicates improvement in heat transfer in the evaporator. The variation in the condensing temperature between the pre-test and the post-test was 0.33 %. The variation in the condensing pressure between the pre-test and the post-test was 0.4 %. These variations can be considered as insignificant and, hence, the condensing temperature and pressure can be assumed to be constant for both tests. CONCLUSION The tests carried out on the Fujitsu heat pump, Model AOT12LSAC indicated an improvement in the cooling capacity of 17.4%, a decrease in power input of 9.7% and an overall increase in system performance of 31% after treatment with PermaFrost. The increase in cooling capacity and system performance will result in the compressor using less energy to achieve the same cooling effect on the unit as prior to treatment with Permafrost. The tests showed that for the 10-hour run time on the unit with the heaters in the room as simulated load the power consumption decrease from 6.2 kwh to 5.6 kwh. This represents an energy saving of 9.7%. In practice, the load in the room will vary rather than remain constant as during the tests with the simulated heat load, the heat pump will cycle on and off as the room reaches the set temperature. Hence, with the increase in cooling capacity and system performance after treatment with PermaFrost, the compressor actual run time will be shorter and the energy saving will be greater than the 9.7% achieved during the post test. The salient results are summarised in the bar graphs in Appendix B.

6 Pre Treatment Test July 3, 2008 Appendix A

7 Chart 1A - TAFE, Regency Park SA - Fujitsu R410A Inverter Performance Measurement, Pre PermaFrost 10 Mean value = 3.16 POWER INPUT [kw] Mean value = 0.62 kw COOLING CAPACITY [kw] Mean value = 3.16 kw 9 Before PermaFrost Value July 3, 2008

8 40 Chart 2A - TAFE, Regency Park SA Fujitsu R410A Inverter Operating Temperatures, Pre PermaFrost ROOM TEMP C AMBIENT TEMP C EVAP TEMP C Mean value = C Mean value = C Mean value = C Before PermaFrost Temp [ C] July 3, 2008

9 Chart 3A - TAFE, Regency Park SA Fujitsu R410A Inverter Operating Temperatures, Pre PermaFrost 70 COND C DISCH C Mean value = C Mean value =58.11 C Before PermaFrost Temp C July 3, 2008

10 30 Chart 4A - TAFE, Regency Park SA Fujitsu R410A Inverter Operating Temperatures, Pre PermaFrost EVAP PRESS Bar COND PRESS Bar Mean value = 8.59 Bar Mean value = Bar Before PermaFrost Temp C July 3, 2008

11 Post Treatment Test July 4, 2008 Appendix A

12 10 9 Chart 1B - TAFE, Regency Park SA Fujitsu R410A Inverter Performance Measurement, Post PermaFrost POWER INPUT [kw] COOLING CAPACITY kw Mean value = 3.71 Mean value = 0.56 kw Mean value = 3.71 kw AfterPermaFrost t Value July 4, 2008

13 40 Chart 2B - TAFE, Regency Park SA Fujitsu R410A Inverter Operating Temperatures, Post PermaFrost ROOM TEMP C AMBIENT TEMP C EVAP TEMP C Mean value = C Mean value = C Mean value = 16.3 C AfterPermaFrost Temp [ C] July 4, 2008

14 65 Chart 3B - TAFE, Regency Park SA Fujitsu R410A Inverter Operating Temperatures, Post PermaFrost COND C DISCH C Mean value =50.94 C Mean value = C AfterPermaFrost Temp C July 4, 2008

15 30 Mean value = 8.84 Bar Chart 4B - TAFE, Regency Park SA Fujitsu R410A Inverter Operating Temperatures, Post PermaFrost EVAP PRESS Bar COND PRESS Bar Mean value = 22.5 Bar AfterPermaFrost Temp C July 4, 2008

16 Performance Comparison Pre: July 3, 2008 & Post: July 4, 2008 Appendix B

17 TAFE, Regency Park SA - Fujitsu R410A Inverter Pre & Post PermaFrost Comparison, Cooling Capacity Cooling Capacity (kw) Linear (Cooling Capacity (kw)) kw Pre treatment Post treatment

18 TAFE, RegencyPark SA Fujitsu R410AInverter Pre & Post PermaFrost Comparison, System Performance Cooling Capacity (kw) Power Input (kw) Value Pre treatment Post treatment