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3. Piping and Connections
ALL
components/materials
must conform
to National Fuel Gas Code Specifications ANSI Z223.1-LATEST
EDITION, or in Canada, CAN/CGA-B149.1-M91 (Natural Gas) or CAN/CGA-B149.2-M91 (Liquid
Propane [L.P.] Gas) or LATEST EDITION (for General Installation and Gas Plumbing), as well as local
codes and ordinances and
must be
done by a qualified professional. It is important that gas pressure
regulators meet applicable pressure requirements, and that gas meters be rated for the total amount of
ALL
the appliance BTUs being supplied.
The dryer is provided with a 1-inch N.P.T. inlet pipe connection extending out the back area of the burner
box. The minimum pipe size connection (supply line) to the dryer is 1-inch N.P.T. For ease of servicing, the
gas supply line of each dryer must have its own shutoff valve.
The size of the main gas supply line (header) will vary depending on the distance this line travels from the
gas meter or, in the case of L.P. gas, the supply tank, other gas operated appliances on the same supply line,
etc. Specific information regarding supply line size
should be
determined by the gas supplier.
NOTE:
Undersized gas supply piping can create a low or inconsistent pressure, which will result in
erratic operation of the burner ignition system.
Consistent gas pressure is essential at
ALL
gas connections. It is recommended that a 1-inch (2.54 cm)
pipe gas loop be installed in the supply line servicing a bank of dryers. An in-line pressure regulator
must be
installed in the gas supply line (header) if the (natural) gas pressure exceeds 12.0 inches (29.9 mb) of water
column (W.C.) pressure.
IMPORTANT:
A water column pressure of 3.5 inches (8.7 mb) for natural gas and 10.5 inches
(26.1 mb) for L.P. dryers is required at the gas valve pressure tap of each dryer for
proper and safe operation.
A 1/8-inch N.P.T. plugged tap, accessible for a test gauge connection,
must be
installed in the main gas
supply line immediately upstream of each dryer.
IMPORTANT:
Pipe joint compounds that resist the action of natural and L.P. gases
must be
used.
IMPORTANT:
Test
ALL
connections for leaks by brushing on a soapy water solution (liquid
detergent works well).
WARNING: NEVER TEST FOR GAS LEAKS WITH A FLAME!!!
ALL
components/materials
must conform
to National Fuel Gas Code Specifications ANSI Z223.1-LATEST
EDITION, or in Canada, CAN/CGA-B149.1-M91 (Natural Gas) or CAN/CGA-B149.2-M91 (L.P. Gas)
or LATEST EDITION (for General Installation and Gas Plumbing), as well as local codes and ordinances
and
must be
done by a qualified professional. It is important that gas pressure regulators meet applicable
pressure requirements, and that gas meters be rated for the total amount of
ALL
the appliance BTUs being
supplied.
IMPORTANT:
The dryer and its individual shutoff valve
must be
disconnected from the gas supply
piping system during any pressure testing of that system at test pressures in excess of
1/2 psig (3.5 kPa).
Summary of Contents for AD-81 II
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