23
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 liquid propane [L.P.] gas, the supply tank), the number of tees, other
gas-operated appliances on the 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 3/4 (19.05 mm)
pipe loop be installed in the supply line servicing the bank of dryers. An in-line pressure regulator
must be
installed in the gas supply line (header) if (natural) gas line pressure exceeds 12.0 inches (29.9 mb) water
column (W.C.) pressure. Refer to the
illustration
on
page 24
for details.
IMPORTANT:
Water column pressure of 3.5 inches (8.7 mb) for natural gas dryers and 10.5 inches
(26.1 mb) for L.P. gas 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.
WARNING:
Test
ALL
connections for leaks by brushing on a soapy water solution (liquid detergent
also works well).
NEVER
TEST
FOR
GAS
LEAKS
WITH
AN
OPEN
FLAME!!!