American Dryer Corp ML-410 manual

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 piping to the dryer must include a 12-inch (30.48 cm) rise 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.Shut-off 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 which will pass 2,700 lbs/hr (1224.69 kg/hr) at 125 psi (8.6 bars) and a check valve at least 12-inches (30.48 cm) below the steam coil as close to the coil as possible.

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 (0.64 cm) for every 1 foot (0.30 meters) back towards the steam supply header causing the condensate in the line to drain the header. Install a bypass trap in any low point to eliminate wet steam.

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