Nortek MG1 Series, Руководство по установке

Страница: 19 / 32

19
Conversion to Propane (LP) Gas
WARNING:
This furnace was shipped from the factory
equipped to operate on natural gas. Conversion
to LP/propane gas must be performed by qualified
service personnel using factory supplied
conversion parts. Failure to use the proper
conversion kit can cause fire, explosion, property
damage, carbon monoxide poisoning, personal
injury, or death.
WARNING:
Shut off the gas supply at the manual gas shutoff
valve, before disconnecting the electrical power.
A fire or explosion may result causing property
damage, personal injury or loss of life. Failure to
follow the safety warnings exactly could result in
serious injury, death or property damage.
WARNING:
To avoid electric shock, personal injury, or death,
turn off the electric power at the disconnect or the
main service panel before making any electrical
connections.
This furnace can be converted from factory-equipped
natural gas to liquid propane gas. Conversion of this valve
requires replacement of the burner orifice and flipping the
regulator cap to the side marked LP. The orifice required
for conversion is supplied with the furnace. See Figure 27 .
For altitudes between 0 and 1,999 feet, use the factory
supplied LP orifice as shown in Table 6, (page 17) .
Altitudes between 2,000 and 10,000 feet require the orifice
to be changed. Table 14, (page 29) lists the correct orifice
size and manifold pressure at different altitudes.
Atmospheric & Direct Ignition Furnaces
1. Follow the instructions in “How to Shut Off Gas - Direct
Ignition” on page 21 .
2. Disconnect the gas pipe union and the electrical wires
connected to the gas valve.
3. Remove the gas valve assembly:
4. Remove screw(s) from gas valve bracket. Gas valve and
spud may be removed. Orifice is located at the end of
the spud.
5. Replace the main orifice with the L.P. gas orifice supplied
in the envelope located by the gas valve. Verify the
orifice size matches the nameplate or Table 6, (page
17) .
6. Unscrew the pressure regulator cap and check for the
letters NAT or LP. See Figure 27 (page 17) .
7. Invert the cap and tighten until snug.
8. Reassemble the burner assembly into the furnace.
9. Reconnect the gas piping and electrical wires to the
gas valve.
10. Open the manual shut-off valve and follow the Operating
Instructions on page 20.
Measuring the Supply Gas Pressure
To obtain an accurate pressure reading, turn off all
gas appliances (i.e. Dryers, water heaters, stoves,
etc.) at their ON/OFF control or individual gas valves.
1. Remove the inlet pressure plug from the INLET side
of the gas valve with a 3/16 Allen wrench. See Figure
27 .
2. Install a 1/8 NPT fitting, which is compatible with a
manometer or similar pressure gauge.
3. Connect the manometer or pressure gauge to the inlet
pressure tap.
4. Turn on all electrical power to the furnace.
5. Turn the main gas supply valve (on the outside of the
unit) to the ON position.
6. Start the furnace by adjusting the thermostat to it’s
highest setting. Allow the furnace to run for 10 minutes.
7. Check the incoming gas line pressure. Propane gas
furnaces must be between 11.0”-14.0” W.C. Natural
gas installations must be between 4.5”-10.0” W.C. If
the pressure is not between these specified ranges,
contact your local gas supplier for adjustment.
8. Adjust the thermostat to it’s lowest setting and allow
the unit to cycle off.
9. Turn the main gas supply valve (on the outside of the
unit) to the OFF position.
10. Turn off all electrical power to the furnace.
11. Disconnect the manometer or pressure gauge.
12. Remove the NPT fitting and reinstall the inlet pressure
plug. NOTE: To prevent cross threading, hand tighten
the plug first, then tighten with 3/16 Allen wrench.
Measuring the Manifold Pressure
The manifold pressure must be measured by installing a
pressure gauge (Manometer, Magnehelic Meter, etc.) to
the outlet end of the gas valve.
1. Remove the manifold pressure plug from the outlet side
of the gas valve with a 3/16 Allen wrench.See Figure
27 (page 17) .
2. Install a 1/8 NPT fitting, which is compatible with a
Manometer or similar pressure gauge.
3. Connect the manometer or pressure gauge to the pipe
thread fitting.
4. Start the furnace by adjusting the thermostat 5 degrees
above room temperature. Allow the furnace to operate
for 3 minutes.
5. Measure the manifold pressure on the manometer or
pressure gauge. Compare the measured value to the
value in Table 12, (page 26) , Table 13, (page 26) , or
Table 14, (page 29) .
6. Replace the cap so that the letters facing up represent
the type of gas being used for the furnace. See Figure
27 (page 17) .
7. Adjust the thermostat to its lowest setting.
8. Turn off the main gas supply to the unit at the manual
shut-off valve, which is located outside of the unit.
9. Turn off all of the electrical power to the furnace.