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4-14
4. Acid proof pump and containers, or bottles with
rubber hose.
What You Will Do --- (Summary)
:
1. Drain water from condenser tubing circuit. Clean
water tubes with Oakite No. 22 to remove mud and slime.
2. Flush.
3. De-scale water tubes with Oakite No. 32 to remove
scale.
4. Flush.
5. Neutralize.
6. Flush.
7. Put unit back in service under normal load and check
head (discharge) pressure.
Detailed Procedure:
1. Drain and flush the water circuit of the condenser
coil. If scale on the tube inner surfaces is accompanied by
slime, a thorough cleaning is necessary before de-scaling
process can be accomplished.
2. To remove slime or mud, use Oakite composition No.
22, mixed 170 grams (6 ounces) per 3.785 liters (1 U.S.
gallon) of water. Warm this solution and circulate through
the tubes until all slime and mud has been removed.
3. After cleaning, flush tubes thoroughly with fresh
clean water.
4. Prepare a 15% by volume solution for de-scaling, by
diluting Oakite compound No. 32 with water. This is
accomplished by slowly adding 0.47 liter (1 U.S. pint) of the
acid (Oakite No. 32) to 2.8 liters (3 U.S. quarts) of water.
WARNING
Oakite No. 32 is an acid --- therefore be sure that
the acid is slowly added to the water. DO NOT
PUT WATER INTO THE ACID! --- this will
cause spattering and excessive heat.
Wear rubber gloves and wash the solution from
the skin immediately if accidental contact
occurs. Do not allow the solution to splash onto
concrete.
5. Fill the tubes with this solution by filling from the
bottom. See Figure 4-18A. Important: --- be sure to
provide a vent at the top for escaping gas.
6. Allow the Oakite No. 32 solution to soak in the tube
coils for several hours, periodically pump-circulating it
with an acid-proof pump.
An alternate method may be used, whereby a bottle
(See Figure 4-18B) filled with the solution and attached to
the coils by a hose can serve the same purpose, by raising
and lowering of the bottle. The solution must contact the
scale at every point for thorough de-scaling, therefore
ensure that no air pockets exist, by regularly opening the
vent to release gas.
Keep flames away from the vent gases.
Fill condenser with
cleaning solution. Do
not add solution more
rapidly than vent can
exhaust gases caused
by chemical action.
Centrifugal pump
30 GPM at 35’ head
Pump
Suction
Pump
support
Tank
Fine mesh
screen
Return
Remove water
regulating valve
Condenser
Globe
valves
Gas
vent
Close vent pipe
valve when pump
is running.
Priming
connection
A --- Forced Circulation
Condenser
Vent
pipe
1” Pipe
5’ Approximate
3’ to 4’
B --- Gravity Circulation
Figure 4-18. Water-Cooled Condenser Cleaning
7. The time required for de-scaling will vary, depending
upon the extent of the deposits. One way to determine
when de-scaling has been completed is to titrate the
solution periodically, using titrating equipment provided
free by the Oakite Technical Service representative. As
scale is being dissolved, titrate readings will indicate that
the Oakite No. 32 solution is losing strength. When the
reading remains constant for a reasonable time, this is an
indication that scale has been dissolved.
8. When de-scaling is complete, drain the solution and
flush thoroughly with water.
9. Next circulate a 56.7 gram (2 ounce) per 3.785 liter (1
U.S. gallon) solution of Oakite No. 22 thru the tubes to
neutralize. Drain this solution.
10. Flush the tubes thoroughly with fresh water.
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