TM 9-4940-556-14&P
4.1.7.3 Depress BLOW-DOWN button and hold in.
4.1.7.4 After outlet temperature reads 250F, lift float rod (interrupting
the flow of water through the unit) and hold for 1 minute after tank empties.
4.1.7.5 Release float rod and BLOW-DOWN button.
4.1.7.6 Allow unit to run till coil outlet temperature is 100F ---- shut
unit OFF.
4.1.7.7 Install steam hose in machine outlet.
4.1.8 Descaling Instructions.
4.1.8.1 Mineral deposits in the coil and coil outlet fittings assembly are
the result of the affects of heat on un-dissolved solids in the water used.
These deposits must be periodically removed to prevent the coil from being
clogged.
4.1.8.2 Chemical descaling (deliming) should be attempted only after BLOW-
DOWN procedure has failed to reduce the difference in coil inlet and outlet
pressure to less than 60 psi.
and contains all inhibitors necessary to protect the metal parts of the
equipment on which it is to be used.
4.1.8.4 Before the descaling procedures are started, read and follow all
"DANGER", "WARNING", "CAUTION" and "FIRST AID STATEMENTS".
"DANGER"
4.1.8.4.1
Inhibited coil descaling powder contains "Sulfamic Acid" and is a poison and
a corrosive chemical.
"DANGER"
4.1.8.4.2
"Sulfamic Acid" should not be handled unless the user is properly clothed, in-
cluding rubber boots, rubber apron, rubber gloves and a full face shield. The
user should read and understand the following procedure, along with the pre-
cautions printed on the acid container. "Failure to do so could result in
severe or possible fatal injury to personnel."
"DANGER"
4.1.8.4.3
Operations must be done in a well ventilated area. Carbon dioxide vapors are
released during this procedure. "Injury to personnel may result if proper
ventilation is not provided."
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