Gas Supply And Piping; Attaching Your Furnace - Williams 2509622 Owner's Manual

Installing Your Furnace
Attaching Your Furnace (continued)
After furnace is in position, install rear outlet register as shown in
Figure 12. Have damper in open position when inserting the
assembly. Secure the rear outlet register to speed nuts with the
machine screws furnished.

Gas Supply and Piping

GAS PIPING
The gas control valve, in the furnace, is shipped with a seal over
the gas inlet tapping. Do not remove the seal until ready to
The gas supply line must be of adequate size to handle the Btu/hr.
connect the piping.
requirements and length of the run for the unit being installed.
Determine the minimum pipe size from Figure 17, basing the
length of the run from the gas meter or source to the unit.
WARNING: Danger of property damage, bodily injury or
death. Make sure the furnace is equipped to operate on
the type of gas available. Models designed as natural gas
All piping must comply with local codes and ordinances or with the
are to be used with natural gas only. Models designed for
National Fuel Gas Code (ANSI Z223.1 NFPA No. 54), whichever
use with liquefied petroleum (L.P) gas have orifices sized
applies. (In Canada: CAN/C.G.A B149). Refer to Figure 18 for
for commercially pure propane gas. They cannot be used
the general layout of the unit. It shows the basic fittings needed.
with butane or a mixture of butane and propane.
The following rules apply:
GAS SUPPLY
1. Use new, properly reamed pipe free from chips such as
steel or black iron pipe and fittings or other approved by
For L.P. gas, the minimum inlet gas supply pressure for the
local codes.
purpose of input adjustment is 11-inches water column. The
maximum inlet gas supply pressure is 13-inches water column.
2. Do not thread pipe too far. Valve distortion or malfunction
may result from excess pipe within the control. Apply a
For natural gas, the minimum inlet gas supply pressure for the
moderate amount of good quality dope to pipe only. Leave
purpose of input adjustment is 5-inches water column.
the two end threads bare. If L.P. gas installation, use
maximum inlet gas supply pressure is 7-inches water column.
compound resistant to action of liquefied petroleum gases.
Gas pressure and input to the burners must not exceed the rated
3. Use ground joint unions.
input and pressure shown on the nameplate. The natural gas
manifold pressure should be 4-inches water column.
4. Install a drip leg (sediment trap) to trap dirt and moisture
manifold pressure should be 10-inches water column for L.P. gas.
before it can enter the gas valve. The nipple must be a
For operation in elevations above 2,000 feet, a burner orifice
minimum of 3-inches long.
change may be required to suit the gas supplied. Check with
5. your local gas supplier. Install a manual shut-off valve.
6. ORIFICE SIZES Provide a 1/8 NPT test gauge connection immediately
before the gas supply connection to the furnace.
The efficiency rating of this appliance is a product thermal
efficiency rating determined
conditions and was determined independently of any installed
Gas Supply and Piping (continued)
system. For elevations above 4,500 feet, reduce ratings 4% for
each 1,000 feet above sea level.
16
under continuous operating
FIGURE 12 – Mounting Rear Outlet Register
Furnace Technical Information
Model
Gas Type
Num ber
2509622 Nat.
2509621 L.P.
3509622 Nat.
3509621 L.P.
5009622 Nat.
5009621 L.P.
Gas Conversion Kits
Natural Gas to L.P. Gas
Model
8901 25096 Series with Williams Brand Gas Valve
8902 35096 Series with Williams Brand Gas Valve
8903 50096 Series with Williams Brand Gas Valve
The
7675 25096 Series with Robertshaw Brand Gas Valve
7676 35096 Series with Robertshaw Brand Gas Valve
7677 50096 Series with Robertshaw Brand Gas Valve
The
Gas Conversion kits
L.P. Gas to Natural Gas
Model
8904
25096 Series with Williams Brand Gas Valve
8905 35096 Series with Williams Brand Gas Valve
8906
50096 Series with Williams Brand Gas Valve
9911 25096 Series with Robertshaw Brand Gas Valve
9912 35096 Series with Robertshaw Brand Gas Valve
9913 50096 Series with Robertshaw Brand Gas Valve
Furnace Technical Inform ation
Heating
Main Burner Orifice
Input
Capacity
Rating
Rating
Btu/hr. Drill
Btu/hr.
25,000 19,350 #43
25,000 19,350 #54
35,000 25,930 #38
35,000 25,930 #52
50,000 38,000 #44
50,000 38,000 #54
Description
Description
Dec. Qty.
0.089 1
0.055 1
0.101 1
0.063 1
0.086 2
0.055 2