should always have an opening at least 12 inches wide. This will allow the thickest end of a manufactured cake of ice, 11>4 inches on a 300-pound size and 11^ inches on a 400-pound cake, to enter without chipping.
Shelves. — The shelf arrangement is an important design feature frequently neglected in refrigerator construction. The ratio of shelf area to food storage volume is a good method of checking this part of the design. Tables LXII and LXIII show that the top icer and ell type refrigerators have practically the same shelf surface for the .same rated ice capacity.
Shelves are usually made of small mesh wire heavily tinned. Glass shelves are used to a limited extent. Some <Callout type="important" title="Important">tables list several advantages of wire shelves, including cheapness, light weight, and easy cleaning.</Callout>
Some refrigerators are made with shelf supports adjustable for height. It has been found in actual service that this feature is not used, as the owner evidently does not appreciate the advantage of spacing the shelves to conform with certain requirements.
TABLE LXIV.— INSULATORS USED IN REFRIGERATORS. Wood 42 Air Space 28 Paper 28 Granulated Cork 13 Mineral Wood 12 Corkboard 8 Flax Composition 6 Felt Paper 2 Cocoa Fiber 1 Vegetable Fiber 1 Eel Grass 1 Hairfelt 1 Wood Fiber 1 Sea Grass 1 The shelf spacing in cabinets using mechanical refrigeration is usually closer than on refrigerators using ice. This close spacing is permissible because of the colder temperature and more active circulation.
Materials for Refrigerators. — The insulating materials used in standard refrigerators are listed in Table LXIV. The foregoing indicates the number of times each insulat- ing material was used in the construction used by 50 different manufacturers. Table LXV shows the woods used in 50 standard refrigerators for outside case and linings :
TABLE LXV.— WOODS USED IN REFRIGERATORS. Oak 21 Ash 13 Fir or Spruce 7 Yellow Pine , White Pine Black Ash Poplar Cypress Birch Table LXVI gives a list of some of the woods which are suitable for refrigerator construction. The botanical name and localitv where such wood grows are included also.
Ice Capacity of a Refrigerator. — The ice capacity of a refrigerator is an arbitrary figure at the best, inasmuch as the pieces of ice that are put into it vary considerably in size and so make more or less waste space. Ice capacities in refrigerators are usually figured in the following way : The cubic inches of ice chamber divided by 1,728 gives total cubic feet and this multiplied by 57.5, which is the weight of a cubic foot of ice, gives the total ice capacity in terms of pounds of ice. From this deduct 25 per cent, considered as a fair allowance for waste space or irregular shaped ice, and the remainder is the figure of ice capacity of a refrigerator.
TABLE LXVII.— RATED ICE CAPACITIES OF REFRIGERATORS. Summary of Data on 473 Different Standard Models. (.Side leers.) Total Inside j Average Rated | Maximum Rated I Minimum Rated Volume I Ice Capacity ; Ice Capacity ) Ice Capacity Cubic Feet. | Pounds. | Pounds. | Pounds. 4— S 58 75 40 5—6 81 110 50 6—7 93 110 50 7—8 103 125 50 8—10 126 200 65 10—12 142 200 75 12—16 177 250 85 16—20 204 300 150 20—24 244 375 170 24—30 284 350 235 30—40 310 425 190 40—60 420 550 300 Table LXVII gi es the rated ice capacities of refrigerators obtained from the data on 473 different standard models of side icer refrigerators. Data are given for refrigerators hav- ing volumes varying from 4 cubic feet to 60 cubic feet.
<Callout type="risk" title="Risk">Note that the ice capacity is an arbitrary figure, and actual storage space may vary.</Callout>
Table LXVIII gives similar rated ice capacities from data on 88 different models of the top icer lift lid icing door construction. TABLE L.WIIL — RATED ICE CAPACITIES OF REFRIGERATORS. Summary of Data on 88 Different Models (Top leers, Life Lid Icing Doorj, Total Inside | Average Rated | Maximum Rated I Minimum Rated Volume I Ice Capacity 1 Ice Capacity | Ice Capacity Cubic Feet. | Pounds. ( Pounds. | Pounds. 3—4 56 120 40 4—5 69 151 65 5—6 92 117 75 6—7 106 133 69 7—9, 133 188 100 8—9 105 110 100 9—10 124 150 100 10—11 150 150 150
Table LXIX gives additional rated ice capacities of refrigerators. The data in this table was obtained from an average of information on 282 different models of the top icer con- struction, includinj^ both lift lid and front door icers.
TABLE LXX.— RATED ICE CAPACITIES OF REFRIGERATORS Summary of Data on 194 Different Standard Models. (T'op Icers, Icing Door on Front). Total Inside I Average Rated | Maximum Rated I Minimum Rated Volume I Ice Capacity | Ice Capacity 1 Ice Capacity Cubic Feet. | Pounds. | Pounds. | Pounds. 3-^ 59 100 50 4—5 81 104 ,-)o 5—6 95 135 60 6—7 113 190 65 7—8 120 176 60 8—9 125 165 75 9—10 154 175 140 10—11 172 224 125 11—12 142 220 110 12—15 194 235 160 15—22 224 350 150
Table LXXI gives some interesting information on ice refrigerators of the ell type construction. Three sizes, 75, 100, and 200 pounds rated ice capacity, are included.
<Callout type="important" title="Important">It is important to note that shelf area, per cent of ice storage space used at rated ice capacity, and the ratio of the shelf area to the food storage volume vary significantly between different models.</Callout>
TABLE LXXI.^-ICE REFRIGERATOR CABINET DATA: ELL TYPE. Rated Ice Capacity Pounds 75 100 200 Outside Dimensions Ice Compartment Width Inches Depth Height Width Inches Depth Height Cu. Ft. Cu. Ft. Ft. Total Volume Overall Food Storage Space Ice Storage Space Cu. Shelf Area. Sq. Ft. Percent Ice Storage Space used at Rated Ice Capacity Percentage of Inside Volume for Ice Storage Shipping Weight (Pounds) Ratio of Shelf Area to Food Storage Volume 32.0 18.6 43.0 12.4 13.6 17.3 14.9 3.6 1.7 5.5 77.1 32. 214 1.53 34.6 20.6 46.4 13.1 15.0 19.7 19.2 5.0 2.2 7.2 79.6 31. 293 1.45 43.4 24.6 56.0 17.3 18.9 26.1 35.5 10.5 5.9 14.1 59.1 36. 477 1.34 This table is computed from ten standard refrigeratort with baked porcelain one piece linings.
TABLE LXXII.— ICE REFRIGERATOR CABINET DATA: TOP ICER. Rated Ice Capacity Pounds I SO 75 100 Outside Dimensions Ice Compartment Width Depth Height Width Depth Height Cu. Ft Cu Cu Inches Inches Ft. Ft. Total Volume Overall Food Storage Space Ice Storage Space Shelf Area Sq. Ft. Percent Ice Storage Space used at Rated Ice Capacity Percent of Inside Volume used for Ice Storage Shipping Weight, pounds Ratio of Shelf Area to Food Storage Volume. 23.4 26.3 29.1 16.3 17.7 18.9 41.4 43.7 48.1 15.8 18.9 21.7 10.8 12.4 13.3 10.3 11.7 12.9 9.1 12.3 15.3 1.94 2.9 3.8 1.02 1.59 2.15 4.3 5.6 6.8 85.8 82.4 81.3 34.5 35.5 36.2 43 173 215 2.22 1.93 1.79 This table is computed from ten standard refrigerators with baked porcelain one piece linings.
<Callout type="tip" title="Tip">Wire shelves are preferred for their ease of cleaning and ability to allow free air circulation, making them a practical choice even today.</Callout>
Household Refrigeration 375 ICE REfRKERATOR CABINET OATA From 10 Standard Make. Refriqelrators of each type 5 00 RATED iCEXAPACITY (pounds) FIG. 203.— ICE REFRIGERATOR CABINET DATA.
ICE REFRIGIRATOR CABINET DATA From 10 Standard Make. Refrigerators of each type HEMFirajHtl^ SO 15 RATED ICE CAPACITY (pounds) FIG. 204.--ICE REFRIGERATOR CABINET DATA.
Key Takeaways
- The ice capacity of a refrigerator is an arbitrary figure and can vary based on the size and shape of the ice pieces used.
- Wire shelves offer several advantages, including ease of cleaning and allowing free air circulation.
- Shelf spacing in refrigerators using mechanical refrigeration is closer than those using ice.
Practical Tips
- Use wire shelves for your refrigerator to ensure easy cleaning and better air circulation.
- Ensure that the opening size on your refrigerator allows for thick ice cakes without chipping.
- Consider the ratio of shelf area to food storage volume when designing or choosing a refrigerator.
Warnings & Risks
- Be aware that the ice capacity is an arbitrary figure, so actual storage space may vary.
- Adjustable shelf supports are not commonly used and may not be practical for most users.
- The insulating materials listed in the chapter can degrade over time, leading to reduced efficiency.
Modern Application
While the specific designs and materials discussed in this chapter have evolved significantly since 1927, understanding the principles of refrigerator design remains crucial. The importance of proper shelf spacing, efficient insulation, and easy-to-clean components still applies today. Modern refrigerators incorporate these concepts with advanced technology to provide better performance and energy efficiency.
Frequently Asked Questions
Q: What is the ice capacity of a refrigerator based on?
The ice capacity of a refrigerator is calculated by dividing the cubic inches of the ice chamber by 1,728 to get total cubic feet, then multiplying that by 57.5 (the weight of a cubic foot of ice), and finally deducting 25% for waste space or irregularly shaped ice.
Q: Why are wire shelves preferred in refrigerators?
Wire shelves offer several advantages such as being cheap to construct, lightweight, easily removable and cleanable, allowing free air circulation, and not getting damaged by heavy food containers. These features make them a practical choice for modern refrigerators as well.
Q: What are some common insulating materials used in refrigerators?
Common insulating materials include wood, air space, paper, granulated cork, mineral wool, corkboard, flax composition, felt paper, cocoa fiber, vegetable fiber, eel grass, hairfelt, and wood fiber. These materials help maintain the cold temperature inside the refrigerator.