Lennox International Inc Gas-Fired Hot Water Boiler GAS Supply Piping, Gas Pipe Sizes

9 - GAS SUPPLY PIPING

!CAUTION

WHAT TO DO IF YOU SMELL GAS

•Do not try to light any appliance.

•Do not touch any electrical switch; do not use any phone in your building.

•Immediately call your gas supplier from a neighbor’s phone. Follow gas supplier’s instructions.

•If you cannot reach your gas supplier, call the fire department.

CHECK GAS SUPPLY

Gas pipe to your boiler must be correct size for length of run and for total BTU per hour input of all gas utilization equipment connected to it. See Table

5 for proper size. Be sure your gas line complies with local codes and gas company requirements.

CONNECTING THE GAS PIPING See Figure 11. Gas line enters boiler from right side.

•Use piping materials and joining methods acceptable to authority having jurisdiction. In absence of such requirements:

•USA - National Fuel gas Code, ANSI Z223.1/NFPA 54

•Canada - Natural Gas and Propane Installation Code, CAN/CSA B149.1

•Use pipe joint compound suitable for LP gas on male threads only.

•Use ground joint unions.

•Install sediment trap upstream of gas controls.

•Use two pipe wrenches when making connection to gas valve to keep it from turning.

•Install manual shut-off valve in vertical pipe about 5 feet above floor.

•Tighten all joints securely.

•Propane gas connections should only be made by licensed propane installer.

•Two-stage regulation should be used by propane installer.

•Propane gas piping should be checked out by propane installer.

CHECKING GAS PIPING

!DANGER

Fire Hazard. Do not use matches, candles, open

flames, or other methods providing ignition source. Failure to comply will result in death or serious injury.

Pressure test boiler and gas connection before placing boiler in operation.

•Pressure test over 1/2 psig (3.5 kPa). Disconnect boiler and its individual gas shutoff valve from gas supply system.

•Pressure test at 1/2 psig (3.5 kPa) or less. Isolate boiler from gas supply system by closing manual gas shutoff valve.

•Locate leakage using gas detector, noncorrosive detection fluid, or other leak detection method acceptable to authority having jurisdiction. Do not use matches, candles, open flames, or other methods providing ignition source.

•Correct leaks immediately and retest.

Table 5 - Gas Pipe Sizes

NATURAL GAS

	Pipe Capacity - BTU Per Hour Input
		Includes Fittings
Length of	½”	¾”	1”	1¼”
Pipe - FT
20	92,000	190,000	350,000	625,000
40	63,000	130,000	245,000	445,000
60	50,000	105,000	195,000	365,000

PROPANE GAS

	Pipe Capacity - BTU Per Hour Input
		Includes Fittings
Length of	Copper Tubing *		Iron Pipe
Pipe - FT	⅝”	¾”	½”	¾”
20	131,000	216,000	189,000	393,000
40	90,000	145,000	129,000	267,000
60	72,000	121,000	103,000	217,000

* Outside diameter

Measure length of pipe or tubing from gas meter or propane second stage regulator.

Figure 11 - Gas Piping

14