113335 - 12
www.amdry.com
17
Type of Gas
Manifold Pressure
*
In-Line Pressure
Natural
3.5 in
wc
6.0 - 12.0 in wc
8.7 mb
14.92 - 29.9 mb
Liquid
Propane
10.5 in wc
11.0 in wc
26.1 mb
27.4 mb
Technical Gas Data
Gas Specifications
Shaded areas are stated in metric equivalents
* Measured at outlet side of gas valve pressure tap when gas valve is on.
Gas Connections:
Inlet connection ............... 1” N.P.T.
Inlet supply size ............... 1” diameter pipe (minimum)
Btu/hr input (per dryer) .... 375,000 (94,500 kcal/hr)
Natural Gas
Regulation is controlled by the dryer’s gas valve’s internal
regulator. Incoming supply pressure must be consistent
between a minimum of 6.0 in wc (14.92 mb) and a maximum
of 12.0 in wc (29.9 mb) pressure.
L.P. Gas
Dryers made for use with L.P. gas have the gas valve’s internal
pressure regulator blocked open so that the gas pressure
must be regulated upstream of the dryer. The pressure
measured at each gas valve pressure tap must be a
consistent 10.5 in wc (26.1 mb). There is no regulator or
regulation provided in an L.P. dryer. The water column
pressure must be regulated at the source (L.P. tank) or an
external regulator must be added to each dryer.
Shaded area is stated in metric equivalent
* D.M.S. equivalents are as follows:
Natural Gas ........................... #4 = 0.2090” (5.3086 mm).
L.P. Gas ................................ #30 = 0.1285” (3.2639 mm).
Shaded area is stated in metric equivalent
* D.M.S. equivalents are as follows:
Natural Gas ........................... #12 = 0.1890” (4.8006 mm).
L.P. Gas ................................ #33 = 0.1130” (2.8702 mm).
ML-130
TYPE OF GAS
Btu/hr
Rating
kcal/hr
Rating
Natural
Liquid Propane
Qty.
D.M.S.
*
Part No.
Qty.
D.M.S.
*
Part No.
375,000
94,500
3
#4
140832
3
#30
140819
Liquid Propane Conversion Kit Part Number 881868
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” 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” diameter.
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 in
wc (29.9 mb) pressure.
IMPORTANT: A water column 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.
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 and L.P. gases must be used.
Test all connections for leaks by brushing on a soapy
water solution (liquid detergent works well).
ML-130DR
TYPE OF GAS
Btu/hr
Rating
kcal/hr
Rating
Natural
Liquid Propane
Qty.
D.M.S.
*
Part No.
Qty.
D.M.S.
*
Part No.
300,000
75,600
3
#12
140863
3
#33
140855
Liquid Propane Conversion Kit Part Number 882626
Never test for leaks with a flame!!!
▲
WARNING
!
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).
