Gas Supply And Piping - Williams AC2030T Owner's Manual

Attaching Your Furnace
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.
FIGURE 12 – MOUNTING REAR OUTLET REGISTER
FURNACE SHIELDS
PLASTER GROUND
REAR REGISTER
OUTLET

Gas Supply and 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 connect the piping.
WARNING: Danger of property damage, bodily
injury or death. Make sure the furnace is equipped to
operate o the type of gas available. Models designed
as natural gas are to be used with natural gas only.
Models designed for use with liquefied petroleum
propane gas have orifices sized for commercially pure
propane gas. They cannot be used with butane or a
mixture of butane and propane.
GAS SUPPLY
For natural gas, the minimum inlet gas supply pressure
for the purpose of input adjustment is 5-inches water
column. The maximum inlet gas supply pressure is
7-inches water column.
For Propane, the minimum inlet gas supply pressure
for the purpose of input adjustment is 11-inches water
column. The maximum inlet gas supply pressure is
13-inches water column
Gas pressure and input to the burners must not exceed
the rated input and pressure shown on the nameplate.
continued
ORIFICE SIZES
The efficiency rating of this appliance is a product Annual
Fuel Utilization Efficiency rating determined under
continuous operating conditions and was determined
independently of any installed system.
This furnace is equipped with a automatically controlled
modulating valve and power burner. For elevations above
2,000 feet, adjust thermostat settings to the appropriate
elevation during installation.
The gas supply line must be of adequate size to handle the
BTU/hr. requirements and length of the run for the unit
being installed.
Determine the minimum pipe size from Figure 13, based on
the length of the run from the gas meter to the unit.
FIGURE 13 - PIPE CAPACITY
LENGTH
OF PIPE
FEET
20
40
60
LENGTH
OF PIPE
FEET
20
40
60
All piping must comply with local codes and ordinances
or with the National Fuel Gas Code (ANSI Z223.1 NFPA No.
54), whichever applies. (In Canada: CAN/C.GA B149). Refer
to FIGURE 14 for the general layout of the unit. It shows the
basic fittings needed.
The following rules apply:
1. Use new, properly reamed steel or black iron pipe and
fittings free of metal chips and debris that are approved by
local codes. Metal chips and debris can damage the valve.
2. Do not thread pipe too far. Valve distortion or malfunction
may result from excess pipe within the gas control valve.
Apply a moderate amount of good quality dope to the
pipe only. Leave the two end threads bare. (Figure 15).
3. Use ground joint unions.
4. Install a drip leg (sediment trap) to trap dirt and moisture
before it can enter the gas valve. The nipple must be a
minimum of 3-inches long.
5. Install a manual shutoff valve.
6. Provide a 1/8" NPT test gauge connection immediately
before the gas supply connection to the furnace.
PIPE CAPACITY - BTU/hr. WITH FITTINGS
NATURAL GAS
PIPE SIZE
3/4"
1/2"
190,000
92,000
130,000
63,000
50,000
105,000
PROPANE
PIPE SIZE
3/4"
1/2"
393,000
189,000
267,000
129,000
103,000
217,000
AC2030 / AC3040 TOP VENT GAS WALL HEATER
1"
350,000
245,000
195,000
1"
732,000
504,000
409,000
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