30 American Dryer Corp. 112144-46
Low-Pressure (up to 15 PSI [1.03 bar]) or High-Pressure (16-125 PSI [1.10 -8.62 bar]) Damper Models
Adherence to the following instructions is necessary to eliminate coil failures due to water hammer caused by wet
steam.
The ADC steam dryer uses a damper system instead of an electric steam valve to control the dryer’s temperature. On
a call for heat, the steam damper opens allowing room air to be drawn through the steam coil, then into the basket
(tumbler). Once the set point temperature has been reached, the steam damper closes and room air now bypasses the
steam coil and passes directly into the basket (tumbler).
The pressure of condensate in the steam supply line will cause water hammer and subsequent heat exchanger failure.
The steam supply connection into the main supply line must be made with a minimum 10-inch (25.4 cm) riser. This
will prevent any condensate from draining towards the dryer.
The steam supply line to the dryer must include a 12-inch (30.48 cm) riser along with a drip trap and check valve.
This will prevent any condensate from entering the steam coil. Flexible hoses or couplings must be used. The dryer
vibrates slightly when it runs and this will cause the steam coil connections to crack if they are hard piped to the
supply and return mains.
Shutoff valves for each dryer should be installed in the supply, return, and drip trap return lines. This will allow the
dryer to be isolated from the supply and return mains if the dryer needs maintenance work.
Install an inverted bucket steam trap and check valve at least 12-inches (30.48 cm) below the steam coil as near to the
coil as possible. A vacuum breaker should be installed in the piping. This will prevent the condensing steam from
causing a vacuum inside the coil possibly damaging the coil. The supply and return lines should be insulated. This
will save energy and provide for the safety of the operator and maintenance personnel.
Water pockets in the supply line, caused by low points, will provide wet steam to the coil possibly causing coil
damage. ALL horizontal runs of steam supply piping should be pitched 1/4” (6.35 mm) every foot (0.30 meter)
back towards the steam supply header causing any condensate in the line to drain to the header. Install a bypass trap
in any low point to eliminate wet steam.
To Next Page
Loading...
Need help?
General
