113403-14 www.amdry.com 25
!
!
Gas Pressure Testing _________________
For proper operation, the gas pressure must be correct,
consistent and maintained at the gas pressure rates shown
on page 21. Provisions are made at the gas valve for taking
gas pressure readings.
There are 2 types of devices used to measure gas pressure.
They are the spring/mechanical type gauge and the
manometer. The use of the spring/mechanical type gauge is
not recommended because they are very easily damaged
and are not always accurate. The preferred type of gauge is
the manometer because it is a simple device to use and is
highly accurate. A manometer is simply a glass or transparent
plastic tube with a scale graduated in inches or millibar. When
it is filled with water and pressure is applied, the water in the
tube rises, showing the exact gas pressure.
Gas Pressure Test Procedure
Turn gas cock in gas supply line to “OFF” position.
50 Hz dryers: Back out miniature screw inside pressure tap
and attach manometer (refer to the illustration on page 23).
60 Hz dryers: Install pressure tap and attach manometer (refer
to the illustration on page 23).
Turn gas cock to “ON” position.
Start the dryer in Heat Mode and wait for ignition. Gas
manifold pressure should be as shown on page 21.
If the gas pressure needs to be adjusted, refer to “Gas
Pressure Adjustment” on page 24.
Once test is complete, turn gas cock to “OFF” position.
Remove manometer. Tighten screw inside the pressure
tap or install plug.
Turn gas cock to “ON” position and check for leaks with soap
solution with main burner “ON.”
Steam Information ____________________
It is your responsibility to have all plumbing connections made
by a qualified professional to ensure that the steam plumbing
installation is adequate and conforms with local, state, and
country regulations or codes.
Care must be exercised when leveling steam dryers into final
position. After leveling the dryer, check the downward pitch
of the heat exchanger from front to rear with a level. Likewise,
check the downward pitch of the return condensate manifold
toward its outlet part. Absence of these downward pitches
will result in probable water hammer and premature heat
exchanger fracture and leakage.
The presence of condensate in the steam will cause water
hammer and subsequent heat exchanger failure. The steam
supply connection must be taken from the top of a
well-dripped steam main. If the supply run-out to the dryer
exceeds 25 feet (7.6 meters), it should be dripped just before
the control valve with a proper trap and dirt pocket.
Important
Failure to comply with the requirements stipulated
in this manual can result in component failure,
which will void the warranty.
Steam Coil pH Level
The normal pH level for copper type steam coils must be
maintained between a value of 8.5 to 9.5. For steel type
steam coils the pH level must be maintained between a value
of 9.5 to 10.5. These limits are set to limit the acid attack of
the steam coils.
Important
Coil failure due to improper pH level will void the
warranty.