The Portland daily press., 1888-02-09
NEW METHOD OF HEATING.
Hot Water for Heating Delivered
Like Gas or Drinking Water.
New York Evening Post


cation of the old Pratt system, has been sue
cessfully started in Boston within the pas
few days. The agent is superheated water
and the pro noters of the scheme say that il
will be the future heating force of this and
other cities. "The tendency of the people Of
this country is towards Capitalization" SAID
the President of the company which has beer
formed for using the system. For many
years people were perfectly contented Il
use their kerosene lamps and candles
Then the gas machine came in, and eacl
householder made his own gas from gasoline
and thought it great convenience. Then
companies were formed to manufacture the
gas at central station and distribute it
through the streets in pipes. People only had
to turn a key and light the gas-n0 trouble
and a great saving in expense. 1t was the
same way with water. The people had their
wells and pumps, and were satisfied for the
time being; but pipes were laid In, water
works were established, and the water was
brought To them, and great saving IN
trouble resulted Weed fires were very well
in their way; they gave place to coal, and
now coal is not displaced, but Is burned at q
central place, and the results are carried in
to the houses. There will be no more trouble
from ashes. etc, and machinery will be run,
houses heated, heat supplied for cooking,
with very little trouble to the householder,
and at less expense than for coal and wood
"By the new system heat is supplied to dis
tant places by means of superheated water
that is. water heated to a higher temperature
than 2l2oF. in space which it completely
fills. No steam is generated, the entire heat
impaired remaining as sensible heat in the
water. In other words, the water is simply a
vehicle for the transmission OF heat, and I'M
der this condition exerts pressure equal to
that which would be exerted by saturated
steam of the same temperature. The plant
cictc nf m n nd
located in a central station, and pipes lead
ing from them in as many directions as may
be required. The boiler is a tubular one.
built in such way as to stand an enormous
pressure.
A four-inch pipe is used, which is connected
with one of the pumps. This pump is con-
nected with the boiler, and the superheated
water is taken from the top of the boiler
and forced through the pipe at a speed vary
second. The pipe is laid in the streets in a
continuous line or loop, which returns to the
station and connects with another pump,
which in turn is connected with the boiler.
BY this means the pipe forms close circuit
of superheated water, whose temperature at
the end where it is returned TO the boiler
again is never allowed to fall below 400oFah-
renheit If none of the water Is used, 1t is,
of course, returned to the boiler again with
out loss except by radiation OF heat, IL any
OF IL is uSeu, It's place mas w NC Hileu ny WI
ter from another source.
SIN addition to the hot-water, or supply
pipe there Is a return water-pipe for the wa
ter which has been used for heating or other
purposes. In this pipe there is no pressure
as under no circumstances is the water which
flows through it over 212oF., and it il rarely
over 1902. This pipe is laid in such way as
to cause natural flow Of the water back to
the central station, where it runs into a re-
ceiving tank and is then pumped into the
boiler, where it is reheated to 1902, or there
abouts, and is sent ON its course again
through the hot-water pipe. By this means
the same water is used over and over again.
In the work which is being successfully OPP
Grated in Boston, the pipes through the
streets were laid with extreme care, and in
a manner which is believed to be the best
that can ne devised.
"The safety of this method of supplying
heat is assured. The supply main is made of
extra heavy pipes, the bursting strain OF
which is 1900 pounds to the square inch
After the main was in place in Boston the
to TIE square inch. Water is delivered to
customers at a temperature of 1902, which
corresponds to about $50 pounds pressure,
and the pressure at no time will exceed 400
pounds, which leaves large margin of safe
ty. As an addltionl precaution a check
valve has been put in each section of pipe,
and in case of a break of any kind only the
water between the two check-valye can es-
cape, as they will close automatically and
the amount of water so escaping will only
be twenty cubic feet which can be easily ia
ken off by the conduit The service is cal
culated to supply heat for any purpose re-
Quiring a temperature of 1902 or less, whether
for cooking, chemical operations, or any
branch of manufacture. The power fur
nished for the Boston Heral, for instance, is
100 horsepower
There are two ways of using this heat in
introduced
ly into q radiator, which may occupy the
same position that the present furnace in the
house does, and heat the air in the same way
the only difference being that a hot-water
coil Is substituted for bed OF Goals. Sec
ondiy, when the house is piped for steam, a
converter is used. The converter resembles
boiler, and the supply pipe leads into it.
Between the converter and the street the
pipe is fitted with reducing valve, which
works automatically. This Is set at the
pressure required for use, and the water is al
lowed to flow into the boiier. where, as soon
as the pressure is removed, the heat contained
in the water converts it into steam. There Is
a steam gauge on the side Of the converter
which registers the pressure in 1t, and the
setting of the valve is an easy matter A
safety valve also connects with the convert
er, which is ready for use in case the valve
should get out of order. All the exhaust
water runs into the return-pipe and is carried
back to the station. The size iof the convert
en- depends, of course, upon the amount and
pressure of steam required. The most Sc
we're demand upon the system is that for
cooking purposes, where $500 are required
By using this method a constant heat can be
obtained in an oven, and schedule of time
necessary to cook any article of food could
be determined.
"The system is much more economical than
steam, as there is no waste. The pipes can
be made much smaller, and, in consequence,
tighter and at less cost. 1t is also far
cheaper than coal. In ordinary practices the
water is sent through the pipes at velocity
of about four feet per second, and this may
be increased at will to ten or fifteen feet If
necessary. The end of the supply main
which leads into the boiler after it has been
around the circuit is kept at 1902 constantly.
"There is series of boilers in the central
station, and when the demand for heat is
light only one or two of them need be used
and water sent through the pipes at low
rate of speed. AS the demand increases the
pumps can be sent along faster, new boilers
brought into use, and the heat will remain
constant in the supply pipe. The system
has been working successfully In Boston for
some time"