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open drain valve in return main, turn on burner
and allow condensate to flow to drain until it has
run clear for at least 30 minutes while feeding
water to boiler so as to maintain normal water
level. Turn off burner, drain boiler, open gate
valve in Hartford Loop, then repeat step (a)
above.
5. Make pH or Alkalinity Test.
After boiler and system have been cleaned and
refilled as previously described, test the pH of
the water in the system. This can easily be done
by drawing a small sample of boiler water and
testing hydrion paper which is used in the same
manner as litmus paper, except it gives specific
readings. A color chart on the side of the small
hydrion dispenser gives the reading in pH.
Hydrion paper is inexpensive and obtainable
from any chemical supply house or through your
local druggist. The pH should be higher than 7,
but lower than 11. Add some appropriate water
treatment chemicals, if necessary to bring the pH
within the specified range.
6. Boiler is now ready to be put into service.
G.
BOILER AND SYSTEM CLEANING -
WATER BOILERS
1. Filling of Boiler and System --- General --- In a hot
water heating system, the boiler and entire system
(other than the expansion tank) must be full of water
for satisfactory operation. Water should be added to
the system until the boiler pressure gauge registers
normal system design operating pressure. To insure
that the system is full, water should come out of all
air vents when opened.
2. Boiling Out of Boiler and System. The oil and
grease which accumulate in a new hot water boiler
can be washed out in the following manner.
a. Remove safety relief valve using extreme care
to avoid damaging it.
b. Add an appropriate amount of recommended
boilout compound.
c. Reinstall safety relief valve.
d. Fill the entire system with water.
e. Start firing the boiler.
f. Circulate the water through the entire system.
g. Vent the system, including the radiation.
h. Allow boiler water to reach operating
temperature, if possible.
i. Continue to circulate the water for a few hours.
j. Stop firing the boiler.
k. Drain the system in a manner and to a location
that hot water can be discharged with safety.
l. Remove plugs from all available returns and
wash the water side of the boiler as thoroughly
as possible, using a high-pressure water stream.
m. Refill the system with fresh water.
3. Add appropriate boiler water treatment compounds
as recommended by your local qualified water
treatment company.
4. Make pH or Alkalinity Test.
After boiler and system have been cleaned and
refilled as previously described, test the pH of the
water in the system. This can easily be done by
drawing a small sample of boiler water and testing
with hydrion paper which is used in the same
manner as litmus paper, except it gives specific
readings. A color chart on the side of the small
hydrion dispenser gives the reading in pH. Hydrion
paper is inexpensive and obtainable from any
chemical supply house or thru your local druggist.
The pH should be higher than 7 but lower than 11.
Add some appropriate water treatment chemicals, if
necessary to bring the pH within the specified range.
With this lower level of protection, care must be
exercised to eliminate all of the free oxygen in the
system.
5. Boiler is now ready to be put into service.
H
. FREQUENT WATER ADDITION
IF, DURING NORMAL OPERATION, IT IS NECESSARY
TO ADD WATER MORE FREQUENTLY THAN ONCE A
MONTH, CONSULT A QUALIFIED SERVICE TECHNICIAN
TO CHECK YOUR SYSTEM FOR LEAKS.
SI, PENDANT LE FONCTIONNEMENT NORMAL, IL
EST NÉCESSAIRE D'AJOUTER DE L'EAU PLUS
FRÉQUEMMENT QU'UNE FOIS PAR MOIS, CONSULTEZ
UN TECHNICIEN DE SERVICE QUALIFIÉ POUR VÉRIFIER
VOTRE SYSTÈME POUR LES FUITES.
A leaky system will increase the volume of make-up
water supplied to the boiler which can significantly
shorten the life of the boiler. Entrained in make-up
water are dissolved minerals and oxygen. When the
fresh, cool make-up water is heated in the boiler the
minerals fall out as sediment and the oxygen escapes
as a gas. Both can result in reduced boiler life. The
accumulation of sediment can eventually isolate
the water from contacting the cast iron. When this
happens the cast iron in that area gets extremely hot
and eventually cracks. The presence of free oxygen
in the boiler creates a corrosive atmosphere which, if
the concentration becomes high enough, can corrode
the cast iron through from the inside. Since neither of
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