Lennox International Inc. GWB9-050IH-2 Manuel D’Utilisation

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 7, Page 29 . 
Boiler and its individual shutoff valve must be disconnected 

from gas supply piping system during any system pressure 

testing at test pressures in excess of ½ psig (3.5kpa).
Boiler must be isolated from gas supply piping system 

by closing its individual manual shutoff valve during 

any pressure testing of gas supply piping system at test 

pressures equal to or less than ½ psig (3.50ka).

10” w.c.

14” w.c.

4” w.c.

10” w.c.

See  Figure 19, Page 29  for general layout at boiler. 
Gas line enters boiler from right side jacket panel. 
Boiler is equipped with ½” NPT connection on gas valve for 

supply piping. 
Following rules apply:

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

Size and install gas piping system to provide suffi cient 

gas supply to meet maximum input at not less than 

minimum supply pressure. See  Table 7, Page 29 

Use ground joint unions.

Provide sediment trap up stream of gas valve.

Use two pipe wrenches when making the connection to 

gas valve to keep it from turning.

Install a manual shutoff valve in the vertical pipe about 

5 feet above fl oor. 

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.

• 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 fi re 

department.

  

Fire Hazard.  Do not use matches, candles, open 

fl ames, 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.

• Disconnect boiler and its individual gas shutoff 

valve from gas supply system.

• Isolate boiler from gas supply system by closing 

manual gas shutoff valve. See  Figure 19, 

Page 29 .

• Locate leakage using gas detector, noncorrosive 

detection fl uid, or other leak detection method 

acceptable to authority having jurisdiction.  Do 

not use matches, candles, open fl ames, or other 

methods providing ignition source.

• Correct leaks immediately and retest.