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Product Type Δ T = Td: Source: Hundy, Trott and Welch. Refrigeration and Air Conditioning 4th Ed. (2008)

This document contains information about refrigeration systems for different types of stored products, including recommended temperature and humidity ranges. It provides refrigerant type and pressure control settings for refrigeration cabinets storing various foods from fresh produce to frozen goods. Temperature, humidity and pressure guidelines are given to safely store and preserve the quality of different food products using commercial refrigeration equipment.

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87 views3 pages

Product Type Δ T = Td: Source: Hundy, Trott and Welch. Refrigeration and Air Conditioning 4th Ed. (2008)

This document contains information about refrigeration systems for different types of stored products, including recommended temperature and humidity ranges. It provides refrigerant type and pressure control settings for refrigeration cabinets storing various foods from fresh produce to frozen goods. Temperature, humidity and pressure guidelines are given to safely store and preserve the quality of different food products using commercial refrigeration equipment.

Uploaded by

agama1188
Copyright
© Attribution Non-Commercial (BY-NC)
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
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Product Type

Products that dehydrate quickly, such


as most fruits and vegetable
Products requiring about 85%
saturated air
Products requiring about 80%
saturated air
Materials not sensitive to dehydration

T = TD
4K
6K
8K
10K Upwards

Source: Hundy, Trott and Welch. Refrigeration and Air Conditioning 4th
Ed. (2008)

Product Type
Eggs, Dairy, Produce, Vegetable
Fruit
Cut Meats
Carcass Meats
Cheese, Packaged or Bottled goods
Frozen Goods
Air Conditioning
Source: Australian Refrigeration and Air
Conditioning 2nd Ed. Graham Boyle

Storage
Temp o C
2-4
2
1
2 to 3
3 to 4
-20
23

Moisture %
RH
90 - 95 %
90%
85 - 90 %
82 - 86 %
70 - 80 %
90% approx.
50 - 55 %

TD
Forced
3 to 6 K
6K
5 to 7 K
7 to 9 K
9 to 12 K
5 to 10 K
20 K

TD Natural
8 to 10 K
10 to 12 K
10 to 12 K
12 to 14 K
14 to 16 K
11 to 14 K

THERMAL DATA FOR SOME FOOD PRODUCTS


Product

Freezing
point

Percent
water (%)

above
freezing

Type

Vegetables

Meat

Miscellaneous

Latent
heat
of fusion
(kJ kg-1)

Apples

-2

84

3.6

1.88

280

Bananas

-2

75

3.35

1.76

255

Grapefruit

-2

89

3.81

1.93

293

Peaches
Pineapples
Watermelons

-2
-2
-2

87
85
92

3.78
3.68
4.06

1.93
1.88
2.01

289
285
306

Asparagus
Beans (green)
Cabbage

-1
-1
-1

93
89
92

3.93
3.81
3.93

2.01
1.97
1.97

310
297
306

Carrots

-1

88

3.6

1.88

293

Corn

-1

76

3.35

1.8

251

Peas

-1

74

3.31

1.76

247

Tomatoes

-1

95

3.98

2.01

310

Bacon
Beef

-2
-2

20
75

2.09
3.22

1.26
1.67

71
255

Fish

-2

70

3.18

1.67

276

Lamb

-2

70

3.18

1.67

276

Pork

-2

60

2.85

1.59

197

Veal

-2

63

2.97

1.67

209

Beer
Bread

-2
-2

92
32-37

4.19
2.93

2.01
1.42

301
109-121

Eggs

-3

3.2

1.67

276

Ice cream

Sourced from

below
freezing

(kJ kg-1C-1)

(C)

Fruit

Specific heat

-3 to -18

58-66

3.3

1.88

222

Milk

-1

87.5

3.9

2.05

289

Water

100

4.19

2.05

335

http://www.nzifst.org.nz/unitoperations/appendix7.htm

Suggested Low and High Pressure control settings for commercial refrigeration
Cabinet
Contents

Supply Air
Temperature

Fresh Produce

0 C to 1 C

Dairy Produce

0 C to 2 C

Delicatessen

-2 C to 0 C

Fresh Meat

-4 C to - 3 C

Frozen Food
Frozen Food

-25 C to - 21
C
-31 C to - 26

Refrigerant
Type
R134a
R404A
R22
R134a
R404A
R22
R134a
R404A
R22
R134a
R404A
R22
R404A
R22
R404A

Cycling Pressure Control


Cut out
1.20 bar
3.70 bar
2.90 bar
0.90 bar
2.50 bar
2.40 bar
1.10 bar
3.50 bar
2.70 bar
0.80 bar
2.90 bar
2.20 bar
0.85 bar
0.50 bar
0.65 bar

Source: Danfoss control products data sheet distributed by Kirby

Cut in

Differential

2.2 bar
5.5 bar
4.50 bar
1.70 bar
3.60 bar
3.70 bar
1.70 bar
4.60 bar
3.60 bar
1.60 bar
4.25 bar
3.40 bar
1.80 bar
1.30 bar
1.40 bar

1.0 bar
1.80 bar
1.60 bar
0.80 bar
1.10 bar
1.30 bar
0.60 bar
1.10 bar
0.90 bar
0.80 bar
1.35 bar
1.20 bar
0.95 bar
0.80 bar
0.75 bar

Safety Control
LP Cut
HP Cut
Out
Out
0.60 bar
11.20 bar
2.40 bar
22.20 bar
0.60 bar
11.20 bar
0.55 bar
11.20 bar
2.40 bar
22.20 bar
1.60 bar
19.00 bar
0.65 bar
11.20 bar
2.60 bar
22.20 bar
2.00 bar
19.00 bar
0.35 bar
11.00 bar
2.00 bar
22.20 bar
1.50 bar
19.00 bar
0.25 bar
22.20 bar
0.00 bar
19.00 bar
0.15 bar
22.20 bar

Approximate Pressure
Conversion Factors
100 kPa = 1 bar
100 kPa = 14 psi
101 psi = 7 bar
1 psi = 7 kPa
Conversion
Examples:
LP Cutout = 1.2 bar
= 1.2 x 100 = 120 kPa
HP Cutout = 300 psi
=300 x 7 = 2100 kPa
= 2100/100 = 21 bar

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