ADC AD-25V Installation Manual page 16

Piping 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 (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 Btu being supplied.
The dryer is provided with a 1/2" N.P.T. inlet pipe connection
extending out the back area of the burner box. The minimum
pipe size (supply line) to the dryer is 1/2" pipe. For ease in
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 line, etc. Specific
information regarding supply line size should be determined
by the gas supplier.
16
NOTE: Undersized gas supply piping can create a low or
inconsistent pressure, which will result in erratic operation
of the burner ignition system.
IMPORTANT: This gas dryer is not provided with an
internal gas supply shutoff and an external gas supply
shutoff must be provided.
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 in
WC (29.9 mb) pressure (refer to the illustration below).
NOTE: A water column test pressure of 3.5 in WC (8.7 mb)
for natural gas and 10.5 in WC (26.1 mb) for L.P. dryers is
required at the gas valve pressure tap of each dryer for
proper and safe operation.
American Dryer Corp. 113237 - 15