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Physical Test with Avanti Refrigerator

 

1.  Two thermometers are securely attached (taped) to the inside of the freezer to record their average temperature (every 4 minutes).   

 

2.  The refrigerator/freezer (R/F) is turned off and its door is left open until its inside and outside temperatures are equal. 

 

3.  The R/F's door is then closed and turned On.  Every 4 minutes the temperature inside the freezer is recorded.

 

 


Indoor Test

R/F is Indoors and the Indoor Temperature is 75 F

4 Minute Intervals

Temperature Inside Freezer

1  (4 minutes)

58.5 F

2  (8 minutes)

41.5 F

3  (12 minutes)

32 F

4  (16 minutes)

29 F

5  (20 minutes)

26.5 F

6  (24 minutes)

24 F

 

 

Outdoor Test

R/F is Outdoors and the Outdoor Temperature is 50 F

4 Minute Intervals

Temperature Inside Freezer

1  (4 minutes)

36 F

2  (8 minutes)

22 F

 


 

2/1/06 Second Test

 

For this test the temperature inside the refrigerator was recorded (not the freezer):

 

R/F is Indoors and the Indoor Temperature is 64 F

4 Minute Intervals

Temperature Inside Refrigerator

1  (4 minutes)

63.5

2  (8 minutes)

57.6

3  (12 minutes)

51.3

4  (16 minutes)

45.5

5  (20 minutes)

42.1

6  (24 minutes)

39.4

7  (28 minutes)

37.6

8  (32 minutes)

36.5

9  (36 minutes)

35.4

10  (40 minutes)

34.3

11  (44 minutes)

33.4

12  (48 minutes)

32.4

13  (52 minutes)

32

14 (56 minutes)

31.6

15 (60 minutes)

31.3

16 (64 minutes)

30.9

17 (68 minutes)

30.9

18 (72 minutes)

30.7

 

I then did the same test outdoors.  Before turning the power On, I left the refrigerator's door open to equalize the temperature inside the refrigerator with the outdoor temperature. 

 

R/F is Outdoors and the Outdoor Temperature is 40 F

4 Minute Intervals

Temperature Inside Refrigerator

1  (4 minutes)

39.4

2  (8 minutes)

34.3

3  (12 minutes)

30.7

4  (16 minutes)

27.3

5  (20 minutes)

25.7

6  (24 minutes)

23.5

7  (28 minutes)

23

8  (32 minutes)

21

9  (36 minutes)

21.2

10  (40 minutes)

19.9

11  (44 minutes)

19.4

 

I then let it run outdoors for about 20 minutes and measured the temperature of the freezer (evaporator).  It is 15° F.

 

Energy Savings Rate = H = 1 - (Tw / Ti )2

 

Tw = 40 - 15 = 25° F    and Ti = 64 - 15 = 49° F     Therefore H = 1 - (25/49)2 = 1 - 0.26 = 74%  Energy Savings Rate.

 

Let's compare the data in the two tables.  In the indoor test, the temperature inside the refrigerator went from 39.4° to 30.7° in 48 minutes (12 x four minute intervals).  Therefore in the outdoor test, the temperature inside the refrigerator should go from 39.4° to 30.7° in 48 x 0.26 = 12.5 minutes.  But in the actual test, the temperature declined from 39.4° to 30.7° in just 8 minutes (2 x four minute intervals).  The test results in this case surpassed the result of the equation (instead of 12.5 minutes, it took only 8 minutes). 

 

The same comparison can be made with 34.3° F.  In the indoor case, the temperature declined from 39.4° to 34.3° in 16 minutes (4 x four minute intervals).  In the outdoor case, it went from 39.4° to 34.3° in 4 minutes (1 x four minute interval).  Assuming the compressor is working without any breaks, 4 / 16 = 25%.  Therefore the energy savings rate will be 1 - 25% = 75%, which is very close to the result of the equation.

 

The second test therefore surpassed the result of the equation [ H = 1 - (Tw / Ti )2 ] in one instance and matched it in another instance.  In the first instance, the energy savings rate was greater than the equation indicated.

 

 

 

 

 

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