Comfort-Aire TGRG Series for R-410A - Manual (Page 20)

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 cause noise and damage the con-
trols. A backup wrench is required to be used on the valve to avoid damage.
The capacities of gas pipe of different diameters and lengths in cu. ft. per hr. with pres-
sure drop of 0.5 in. and specific gravity of 0.60 (natural gas) are shown in Table 2.
After determining the pipe length, select the pipe size which will provide the minimum
cubic feet per hour required 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 valve to use liquefied petroleum (LP) gas by replacing the pressure regulator
spring with the conversion kit spring. This LP kit spring allows the regulator to maintain the
proper manifold pressure for LP gas. The correct burner LP orifices are included in the kit.
See Figure 20.
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.
! 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
THIS UNIT IS EQUIPPED AT THE FACTORY FOR USE ON NATURAL GAS ONLY.
CONVERSION TO LP GAS REQUIRES A SPECIAL KIT SUPPLIED BY THE DIS-
TRIBUTOR OR MANUFACTURER. MAILING ADDRESSES ARE LISTED ON THE
FURNACE RATING PLATE, PARTS LIST AND WARRANTY. FAILURE TO USE
THE PROPER CONVERSION KIT CAN CAUSE FIRE, CARBON MONOXIDE POI-
SONING, EXPLOSION, PERSONAL INJURY, PROPERTY DAMAGE OR DEATH.
FIGURE 20
FIGURE 20
20