Image DE 30 Instruction Manual page 33

INSTALLATION PROCEDURES
1. Low – Pressure Steam (10 – 15 psig) Solenoid Valve Models
Adherence to the following instructions is necessary to eliminate coil failures due to water
hammer caused by wet steam.
The presence of condensate in the steam supply 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" riser. This will prevent any condensate from draining towards the dryer.
The steam supply piping to the dryer must include a 12" rise 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.
Shut – off 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 a float and thermostatic steam trap and check valve at least 12" below 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 and 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"
every foot 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. DO NOT elevates the
condensate return line after the float and thermostatic trap. Drain only by gravity into a properly
vented low pressure return line or condensate tank.
Figure.3-18 Low pressure steam supply 15 psig Max
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