Lennox G21Q Series Installation Instructions Manual page 10

3 - - Suspend piping at a minimum of every 5 ft.
(1.52m) using isolation hangers. A suitable hang-
er can be fabricated by putting a sleeve of Arma-
flex refrigeration piping insulation around the pipe
and suspending it using metal strapping as shown
in figure 6. Place a small sheet metal strip between
the Armaflex and the metal strapping to prevent
crimping. Do not secure piping directly to joist or
flooring.
4 - - In areas where piping penetrates joists or interior
walls, hole must be large enough to allow clear-
ance on all sides of pipe through center of hole us-
ing an isolation hanger.
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5 - - Route piping to outside of structure.
with installation following instructions given in ex-
haust and intake piping termination section.
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Insufficient combustion air can cause headaches,
nausea, dizziness or asphyxiation. It will also
cause excess water in the heat exchanger resulting
in rusting and premature heat exchanger failure.
Excessive exposure to contaminated combustion
air will result in safety and performance related
problems. Avoid exposure to the following sub-
stances in the combustion air supply:
Permanent wave solutions
Chlorinated waxes and cleaners
Chlorine base swimming pool chemicals
Water softening chemicals
De-icing salts or chemicals
Carbon tetrachloride
Halogen type refrigerants
Cleaning solvents (such as perchloroethylene)
Printing inks, paint removers, varnishes, etc.
Hydrochloric acid
Cements and glues
Antistatic fabric softeners for clothes dryers
Masonry acid washing materials
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Continue
3DJH 
D - - Removal of the Furnace from Common Vent
If a G21 furnace replaces a furnace which was commonly
vented with another gas appliance, the size of the existing
vent pipe for that gas appliance must be checked. With-
out the heat of the original furnace flue products, the ex-
isting vent pipe is probably oversized for the single water
heater or other appliance. The vent should be checked for
proper draw with the remaining appliance.
The following test should be conducted while all
appliances (both in operation and those not in opera-
tion) are connected to the common venting system. If
the venting system has been installed improperly, the
system must be corrected.
1 - - Seal any unused openings in the common venting
system.
2 - - Visually inspect the venting system from proper size
and horizontal pitch. Determine there is no blockage
or restriction, leakage, corrosion, or other deficien-
cies which could cause an unsafe condition.
3 - - To the extent that it is practical, close all building
doors and windows and all doors between the space
in which the appliances remaining connected to the
common venting system are located and other
spaces of the building. Turn on clothes dryers and
any appliances not connected to the common vent-
ing system. Turn on any exhaust fans, such as range
hoods and bathroom exhausts, so they will operate
at maximum speed. Do not operate a summer ex-
haust fan. Close fireplace dampers.
4 - - Follow the lighting instructions. Place the appliance
being inspected in operation. Adjust thermostat so
appliance will operate continuously.
5 - - Test for spillage of flue gases at the draft hood relief
opening after 5 minutes of main burner operation.
Use the flame of a match or candle, or smoke from a
cigarette, cigar or pipe.
6 - - After determining that each appliance remaining
connected to the common venting system proper-
ly vents when tested as indicated above, return
doors, windows, exhaust fans, fireplace dampers
and any other gas- -burning appliance to their pre-
vious condition of use.
7 - - If improper venting is observed during any of the
above tests, the common venting system must be
corrected. The common venting system should be
resized to approach the minimum size as deter-
mined by using the appropriate tables in appendix
G in the current standards of the National Fuel Gas
Code ANSI Z223.1 in the U.S.A., and the appropri-