Cork insulation; a complete illustrated textbook on cork insulation ...

380 CORK INSULATION j
Household refrigerators, as at present produced, may be 1
dhided into three main classes:
(a) Ice cooled.
(b) Ice or mechanically cooled.
(c) Mechanically cooled. i
It is not, in general, satisfactory to design and build refriger-
ators for dual service; that is, a refrigerator correctly designed
for mechanical cooling may possibly be adjusted to ice, but
the average ice refrigerator, though satisfactory with ice,
usually is not satisfactory when mechanically cooled, for rea- j
sons having to do with temperature and <strong>insulation</strong>, as elabo- j
rated throughout this Chapter, and for still other reasons to be !
noted. Tlie ice cooled refrigerator, on the one hand, aims to :
fulfill one major function:
1. To maintain at a suitable and reasonably uniform temperature a !
compartment for the storing of ]ierishable foodstufifs. i
The mechanically cooled refrigerator, on the other hand, must ;
fulfill an additional major function: I
2. To supply at all times cul)e-ico lor table use. 1
These functions are sufiiciently unrelated, or require sufficient j
correlation, as to make the two types of refrigerators some- ;
what dissimilar in design. Consequentl}', for the present, all
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tests on household refrigeratt)rs should be made from the
standpoint of either ice cooling or mechanical cooling.
Considering first the ice cooled refrigerator, it is well
understood that a "suitable" temperature must of necessity
fall within a higher zone than would be possible with mechan-
ical refrigeration, which higher zone of temperatures has both
its advantages and its disadvantages. It imposes a narrow
limit of safet}' for temperature fluctuations from the zone of
satisfactory temperature operation; ])ut it provides a tem-
perature zone in which miscellaneous "moist foods" may be
stored in the same compartment with the minimum loss of weight
and natural flavor, and, because of the air purifying process
constantly carried on by the absorption of odors by the water
of ice meltage, it guarantees against the tainting of one food
from the odors of another.
The temperature of melting ice being Z2° F., the coldest
air dropping into the t'ood compartment will range from about
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