Installation guide

129098-UIM-H-1011
CONVERSION PROCEDURE
A CAUTION
The gas supply must be shut off prior to disconnecting the electrical
power, before proceeding with the conversion.
AWARNING
SHOCK HAZARD - Turn off electrical supply to furnace.
1. Shut off gas supply at valve upstream from furnace or at meter as
required. Refer to Figure 714.
2. Disconnect gas supply piping from gas valve on furnace.
3. Disconnect electrical wires from gas valve, noting which wires are
connected to which terminals.
4. Remove 4 bolts that attach the gas valve to the 90° flange.
A CAUTION
The rubber “O” ring provided seals the gas valve to the 90° flange.
Make sure it is installed when the gas valve is attached to that
flange.
5. Remove the four screws that attach the gas manifold to the burner
support box. See Figure 15.
6. Remove and discard natural gas orifices.
7. Remove LP (propane) orifices from the bag attached to the gas
valve.
8. Install the LP (propane) gas orifices supplied with the furnace.
Tighten to 15 - 25 inch - pounds of torque.
9. Reinstall the manifold in the assembly by reversing the removal
process.
10. Reconnect the wires to the proper terminals on the gas valve.
11. Remove the regulator with the blue cap and turn it upside down so
the letters “LF” are upright. Place the blue cap on the opposite end
of the regulator.
12. Convert the gas valve for LP (propane) gas operation by following
the instructions. Remove the natural tag and replace with the pro-
pane tag supplied in the orifice bag.
13. Remove the blue conversion label on the furnace door after the
furnace has been converted.
14. Reconnect the gas supply piping to the gas valve and insure that
all gas connections are tight.
15. Remove pressure tap plugs from gas valve and connect water
gauge to the pressure tap ports. See Figure 30 for location of the
gas valve pressure taps and pressure regulator adjustment.
16. Turn on gas supply to furnace and check ail gas connections with
suitable leak detector.
| AWARNING |.
Never use an open flame to check for leaks. Fire or explosion could
occur. Since some leak solutions including soap and water may
cause corrosion or stress cracking, the piping must be rinsed with
water after testing unless it has been determined that the leak test
solution is non-corrosive.
IMPORTANT
When converting gas valve from or to Propane gas, it will be neces-
sary to change main burner orifice to prevent an underfired or over-
fired condition. See label inside lower furnace door for complete
instructions.
HIGH ALTITUDE GAS ORIFICE CONVERSION
This furnace is constructed at the factory for natural gas-fired operation
at 0 — 2,000 ft. (0 m -— 610 m) above sea level.
The gas orifices on this furnace must be changed in order to maintain
proper and safe operation, when the furnace is installed in a location
where the altitude is greater than 2,000 ft. (610 m) above sea level on
natural gas or the altitude is greater than 4,000 ft. (1219 m) above sea
level on propane (LP) gas. Refer to Table 6 or the instructions in the
high altitude conversion kit for the proper gas orifice size.
For Propane gas operation, the furnace is designed for 11" W.C. inlet
gas pressure. Pressure to main burner is then reduced to 10" W.C.
The unit may also be converted for altitudes up to 10,000 ft. (3048 m)
on natural and propane (LP) gas with additional derate as shown in
Table 6 or refer to ANSI 2223.1 NFPA 54 National Fuel Gas Code or in
Canada CAN/CGA-B149.1-00 Natural Gas and Propane Installation
Code.
ADANGER
PROPANE AND HIGH ALTITUDE CONVERSION KITS
It is very important to choose the correct kit and/or gas orifices for
the altitude and the type of gas for which the furnace is being
installed.
Only use natural gas in furnaces designed for natural gas. Only use
propane (LP) gas for furnaces that have been properly converted to
use propane (LP) gas. Do not use this furnace with butane gas.
Incorrect gas orifices or a furnace that has been improperly con-
verted will create an extremely dangerous condition resulting in pre-
mature heat exchanger failure, excessive sooting, high levels of
carbon monoxide, personal injury, property damage, a fire hazard
and/or death.
High altitude and propane (LP) conversions are required in order
for the appliance to satisfactory meet the application.
An authorized distributor or dealer must make all gas conversions.
In Canada, a certified conversion station or other qualified agency,
using factory specified and/or approved parts, must perform the
conversion.
The installer must take every precaution to insure that the furnace
has been converted to the proper gas orifice size when the furnace
is installed. Do not attempt to drill out any orifices to obtain the
proper orifice size. Drilling out a gas orifice will cause misalignment
of the burner flames, causing premature heat exchanger burnout,
high levels of carbon monoxide, excessive sooting, a fire hazard,
personal injury, property damage and/or death.
Johnson Controls Unitary Products 11