2)Liquid Propane (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 inches water column (W.C.) - 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.

 

 

 

 

 

 

Type of Gas

 

L.P.

 

 

 

 

 

 

 

 

 

 

Conversion

 

BTU

 

 

Natural

 

 

Liquid Propane

MODEL

kcal/hr

 

 

 

Kit

Per Hour

 

 

 

 

 

 

 

NUMBER

Rating

Qty.

D.M.S.*

 

Part

Qty.

D.M.S.*

Part

Part Number

Rating

 

Number

Number

 

 

 

 

 

 

 

 

ML-130DR

300,000

75,600

3

#12

 

140863

3

#33

140855

882626

 

 

 

 

 

 

 

 

 

 

 

Shaded area is stated in metric equivalent

* D.M.S. (Drill Material Size) equivalents are as follows:

Natural Gas

#12

= .1890” (4.8006 mm)

Liquid Propane Gas ..

#33

= .1130” (2.8702 mm)

3.Piping/Connections

ALL components/materials must conform to National Gas Code Specifications, or in Canada, the Canadian Installation Codes (for General Installation and Plumbing). 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’s 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 (supply line) to the dryer is 1-inch N.P.T. For ease servicing, the gas supply line of each dryer must have its own shut-off 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. (liquid propane) 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.

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 serving a bank of dryers. An in-line pressure regulator must be installed in the gas supply line (header) if the (natural) gas pressure exceeds 10.5 inches of water column (W.C.) - 26.1 mb - pressure.

NOTE: A water column (W.C.) test pressure of 3.5 inches (8.7 mb) for natural gas and 10.5 inches (26.1 mb) for L.P. (liquid propane) 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.

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American Dryer Corp MLG-130DR (HSI) installation manual Type of Gas, Liquid Propane L.P. Gas