Desert Aire Aura QS, Installation And Operation Manual

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Gas connection sizes are shown in Figure 10. Note that these are connection sizes
only. Supply lines must be sized based on pressure drop and capacity as indicated in
Figure 9.
Model Size
Natural Gas
Propane Gas
100 - 250
1/2”
1/2”
300 - 400
3/4”
1/2”
Figure 10 - Gas Connection Sizes
Gas piping must conform to all applicable codes and standards. Follow standard gas
piping practices, including:
• Pitch gas piping downward in the direction of flow so condensed moisture can
drain freely.
• Install a drip leg at the lowest point in the gas line to prevent moisture and
debris from clogging the gas train. The National Fuel Gas Code requires the
installation of a trap with a minimum of 3” drip leg. Local codes may require a
longer drip leg, typically 6”.
• Install a ground joint union and manual shutoff valve in an accessible position
close to the equipment.
• Ensure that the pipe and fittings are free from chips and debris. Make sure
that the threads are clean and properly cut.
• Seal pipe threads with pipe dope or a suitable joint compound that is
compatible with the gas you are using. Do not use Teflon tape to seal gas
pipe joints.
• Support gas piping using suitable straps or hangers to avoid stressing the gas
valve or manifold.
• Use a backup wrench when you tighten gas pipe and fittings.
• Piping from the natural gas meter to the furnace shall be in accordance with
requirements of the local utility. Piping from the LP tank to the furnace must
follow the recommendations of the gas supplier.
• A readily accessible, certified manual shut off valve with a non-displaceable
rotor member should be installed within six feet of the gas equipment it serves.
Desert Aire - QS/QV Manual