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American Dryer Corp.
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d. Shutoff valves for each dryer should be installed in the supply line, return line, and drip trap return line.
This will allow the dryer to be isolated from the supply main and the return main if the dryer needs
maintenance work.
e. Install an inverted bucket steam trap and check valve at least 12-inches (30.48 cm) below the steam
coil return manifold as close to the coil as possible. A trap with a capacity of 900 lb (408 kg) of
condensate per hour at 125 psi (8.62 bar), is needed for each unit.
f. The supply line and the return line should be insulated. This will save energy and provide for the safety
of the operator and maintenance personnel.
g. Dryers with Optional Steam Solenoid Valve: Mount steam solenoid valve in orientation shown, with coil
up. The supply line should be supported to prevent damage to the steam coil due to the overhung weight
of the steam solenoid valve.
h. Water pockets in the supply line, caused by low points, will provide wet steam to the coil possibly
causing steam coil damage. ALL horizontal runs of steam supply piping should be pitched 1/4-inch
(6.35 mm) for every 1 foot (0.31 meters) back towards the steam supply header causing the condensate
in the line to drain to the header. Install a bypass trap in any low point to eliminate wet steam.
4. Steam Damper Air System Connections
In standard format, this dryer is manufactured with a pneumatic (piston) damper system, which requires an
external supply of compressed air of 3.25 cfh (0.09 cmh) (refer to Section M for further compressed air
requirements). (Note: This dryer may be provided with an optional steam solenoid valve in which case, no
steam damper system is provided.)
