The evening times. [volume] (Washington, D.C.) 1895-1902, 1902-11-24
Turn of Valve Raises or
Lowers Temperature
MAGIC OF MODERN SCIENCE
Plans of Baltimore Refrgerating and
Heating Company as Explained
by One of Officials.

the SNIeelSs stated yesterday Inal Il
proposed TO go ahead as rapidly as pos
sible with the work In further explana-
tion Of the plans Of the company he said:
We have purchased the necessary
properties to complete our plants. and
the work of equipping them will be
prosecuted at once.
"A great deal of interest has been ex-
pressed in the company's plans for dis
tributing heat and cold cont.I ued the
Official. Contrary to general belief,
the refrigerating pipe mains will not be
cold, but Will be at the same tempera-
ture as other mains. such as gas and
water. The pipe line carries what might
be called a cold potential-that is.
means of producing cold OF, more ex-
sctly speaking. the means OF taking up
heat
The pipe lire supplies the means of
continually taking away heat from in
closed areas. This is accomplished ny
means Of liquid anhydrous ammonia,
which is sent out through a main pipe
and connected by branch or service
pipes with the customers refrigerator
is held under pressure in the pipe, so
ii cannot expand or boil or take up any
heat. hence the liquid line. as it is
called, is at the same temperature as
the ground through which it passes.
al the refrigerator the liquid service
pipe IS connected to a coil Of piping in
side OF the refrigerator, called the 'ex-
pansion COLL This coil connects at its
other end with a second service pipe and
second main laid alongside OF the liquid
line. This is called the 'vapor line b.
the action Of the machinery at the cen
tral station a low pressure is main
tanned in the vapor line and the expan-
sion coils connected with it.
"a specially constructed valve allows
the liquid to trickle from the liquid line
where there is pressure into the expan-
sion coils, where the pressure is about
the same as the atmosphere.
The amount Of pipe surface and feed
Of ammonia is so adjusted that all OF
the liquid is boiled TO a gas in the ex-
pansion piping, and all of the refriger-
atlng effect Of the liquid is used up IL
the refrigerator; the gas which leaves
the expansion piping by way Of the
vapor line service pipe has practically
no refrigerating power. hence the vapI-
line is also al or very near the temper
allure OF the ground
The refrigerating machine at the cen
tTal station is continually sucking back
the gas and COMPRISING it into con-
densers, where the heat is squeezed out
of it and taken away by cooling water,
and 1t is Iecondensed TO a liquid and
again sent out through the liquid line
on it's cooling mission. 1t will thus be
seen that the cooling methods are ex-
actly the reverse Of steam-heating oper-
ations.
In steam heating the liquid is boiled
to a gas (steaml at the central station
and sent out as a gas to the radiators
here IL is condensed to a liquid (water)
giving out heat that flows from the
radiator through the air of the room and
through the walls TO the outer cold air
The condensed water may be reboiled 70
steam.
In the refrigerating pipe line a liquid
is sent out to the expansion coils (cor-
is then boiled TO a gas by heat which has
come from the warm outer air through
the walls and air in the refrigerator
This heat is brought back by the gas and
thrown into the sewer by means OF the
cooling water. which takes II away from
the condensers. The gas is again con
densed 10 a liquid.
In order that repairs and extensions
may Be ihace on the line and in and
around the customers refrigerators
third main. ceIled the vacuum main Is
laid alongside the liquid and vapol
mains. This vacuum main has servic,
branches running 20 every refrigerator
II repair or an extension is 10 be made
the expansion piping is cut of from IN,
liquid and vaDor services by valves and
a valve is opened into the vacuum line
The action Of a vacuum pump at ths
central station clear the section OF pip
ing cut on OF the service mains saves
all the ammonia and allows the pfpin.
20 be opened and extended OF repaired
without stoppage OF refrigeration al am
other point and avoiding all SINE II Of am
monia- The vacuum main is also con
nected at all manholes. so that repair.
can be made on the main line. but 8,
carefully is the main line laid and test.
ed that as a matter Of experience re.
pairs are seldom. II ever. necessary.
In the early days OF steam heating ;
return main was laid 10 carry back q
the central stat on the condensed water
from the radiators OF the customers. L
was found that distilled water or the va
ter Of condensation reduced from a higl
temperature attacked the iron or stec
pipe. rendering II worthless in the cours,
OF four or five years. II would not, how
ever. attack cast iron.
The return line was therefore aban
doned. and in it's place what is known a
an economizing coil is used IN eacl
building This coil is placed IN a tin
lined box with a fresh air inlet and
tin-pipe outlet 10 a register in the foo
above. Just the same as IN furnace prac
tice In this way a continual current O
warm, fresl ar Is introduced into tn
building. and all the available heat tina
remains in the water OF condensation /
utilized Il supplement the work OF "a
diators. at the same time securing per
feet ventilation. Modern methods ar
used TO prevent the leakage caused b.
expansion and contraction The eXpe
rience OF a quarter OF a century ha
gradually developed a system Of insula
ton which has practically reached 70
commercial limit and has reduced tn
loss Of heat by radiation 20 from one
fourth CT / per cent 10 per cent. de