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a. The presence of condensate in the steam supply will cause water hammer and subsequent heat exchanger
(steam coil) 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.
b. 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.
c. 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.
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 as
close to the coil as possible.
1) A trap with a capacity of 350 lb (160 kg) of condensate per hour at 125 PSI (8.61 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. 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 (0.30 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.
IMPORTANT: Flexible hoses/couplings must be used. Coil failure due to hard plumbing
connections will VOID THE WARRANTY.
