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Consistent gas pressure is essential at
ALL
gas connections. It is recommended that a 3/4-inch (19.05
mm) 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. (Refer to the illustrations on the previous page.)
NOTE:
A water column test pressure of 3.5 inches (8.7 mb) for natural gas and 10.5 inches (26.2 mb)
for liquid propane (L.P.) dryers is required at the gas valve pressure tap of each dryer for
proper and safe operation.
A 1/8” 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 gas and L.P. gas
must be
used.
IMPORTANT:
Test
ALL
connections for leaks by brushing on a soapy water solution (liquid
detergent works well).
WARNING: NEVER TEST FOR 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).
NOTE:
The dryer
must be
isolated from the gas supply piping system by closing its individual manual
shutoff valve during any pressure test of the gas supply system at test pressures equal to or less
than 1/2 psig (3.5 kPa).
