17
THIS UNIT IS EQUIPPED AT THE
FACTORY FOR USE ON NATURAL
GAS ONLY. CONVERSION TO LP
GAS REQUIRES A SPECIAL KIT
SUPPLIED BY THE DISTRIBUTOR
OR MANUFACTURER. MAILING
ADDRESSES ARE LISTED ON THE
FURNACE RATING PLATE, PARTS
LIST AND WARRANTY. FAILURE
TO USE THE PROPER CONVER-
SION KIT CAN CAUSE FIRE,
CARBON MONOXIDE POISONING,
EXPLOSION, PERSONAL INJURY,
PROPERTY DAMAGE OR DEATH.
WARNING
DO NOT USE AN OPEN FLAME
TO CHECK FOR LEAKS. THE
USE OF AN OPEN FLAME CAN
RESULT IN FIRE, EXPLOSION,
PROPERTY DAMAGE, PERSONAL
INJURY OR DEATH.
WARNING
TO CHECK FOR GAS LEAKS, USE A SOAP AND WATER SOLUTION OR OTHER
APPROVED METHOD. DO NOT USE AN OPEN FLAME.
IMPORTANT:
Check the rating plate to make certain the appliance is equipped to burn
the type of gas supplied. Care should be taken after installation of this equipment that
the gas control valve not be subjected to high gas supply line pressure.
In making gas connections, avoid strains as they may damage the gas controls. A back-
up wrench is required to be used on the valve to avoid damage. Do not overtighten the
connection.
The capacities of gas pipe of different diameters and lengths in cu. ft. per hr. with pres-
sure drop of 0.3 in. and specific gravity of 0.60 (natural gas) are shown in Table 1.
After determining the pipe length, select the pipe size which will provide the minimum
cubic feet per hour re quired for the gas input rating of the furnace. By formula:
Gas Input of Furnace
(BTU/HR)
Cu. Ft. Per Hr. Required =
Heating Value of Gas
(BTU/FT
3
)
The gas input of the furnace is marked on the furnace rating plate. The heating value of
the gas (BTU/FT
3
) may be determined by consulting the local natural gas utility or the
L.P. gas supplier.
B. LP CONVERSION
Convert the unit to use liquefied petroleum (LP) gas by replacing with the stem/spring
assembly supplied in the conversion kit. The LP gas valve maintains the proper manifold
pressure for LP gas. The correct burner LP orifices are included in the kit.
See Figure 18A for component locations.
NOTE:
Order the correct LP conversion kit from the furnace manufacturer.
See
Conversion Kit Index shipped with unit for proper LP kit number. Furnace conver
-
sion to LP gas must be performed by a qualified technician.
!
!
FIGURE 18A
HEAT EXCHANGER COMPONENT IDENTIFICATION
ST-A1125-13