Vent And Combustion Air Piping; Direct Vent; Contaminated Combustion Air - International comfort products C9MVX Installation Instructions Manual

For Two Pipe Installation

(Direct Vent)

This furnace can NOT be common vented or connected to any type
B, BW or L vent or vent connector, nor to any portion of a

Vent and Combustion Air Piping

WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in
personal injury or death.
Use methods described here to provide combustion
and ventilation air.
Dual Certified (*9MPT, *9MPV, *9MVX Models)
Direct or Non-Direct Vent
This furnace is certified as a Category IV furnace. This furnace can
be installed as a direct vent furnace using outside air for
combustion or the furnace can use air from inside the structure for
combustion. The INLET air pipe is optional. If combustion air
comes from inside the structure, adequate make up air MUST be
provided to compensate for oxygen burned. See Confined Space
Installation in the Combustion and Ventilation Air chapter. If
combustion air is drawn from outside the structure, it MUST be
taken from the same atmospheric pressure zone as the vent pipe.

Contaminated Combustion Air

Installations in certain areas or types of structures will increase the
exposure to chemicals or halogens that may harm the furnace.
The following areas or types of structures may contain or have
exposure to the substances listed below. The installation must be
evaluated carefully as it may be necessary to provide outside air for
combustion.
•
Commercial buildings.
•
Buildings with indoor pools.
•
Furnaces installed in laundry rooms.
•
Furnaces installed in hobby or craft rooms.
•
Furnaces installed near chemical storage areas.
•
Permanent wave solutions for hair.
•
Chlorinated waxes and cleaners.
•
Chlorine based 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.
•
Sulfuric Acid.
•
Solvent cements and glues
•
Antistatic fabric softeners for clothes dryers.
•
Masonry acid washing materials.
440 01 2024 04
.
Specifications are subject to change without notice.
factory−built or masonry chimney. If this furnace is replacing a
previously common-vented furnace, it may be necessary to resize
the existing vent and chimney to prevent oversizing problems for
the other remaining appliance(s). See "Venting and Combustion
Air Check" in this section. This furnace MUST be vented to the
outside.
Vent and Combustion Air Piping Guidelines
This furnace is approved for venting with Schedule 40 PVC, CPVC,
ABS fittings, and Cellular Core and SDR−26 PVC pipe.
Applicable ASTM Standards for Vent Materials
Sch. 40 SDR
Materials
Pipe Pipe
ABS D1527 __
PVC D1785 D2241
CPVC F441 F442
ABS to
−− −−
PVC
NOTE: 1) In Canada, all pipe, fittings & cements must
conform to applicable CSA standards or to local codes having
jurisdiction.
2) Only use solvent cements that are marked for use
with the specific venting material.
3) ABS to PVC transition joints REQUIRE a special
solvent cement that meets the requirements of ASTM D3138.
4) Refer to ASTM D2855 for general procedure to
use for cementing plastic pipe and fittings.
NOTE: In order to create a seal that allows future removal of pipe,
RTV sealant MUST be used on the inlet pipe where it joins to the
furnace.
NOTE: All vent piping MUST be installed in compliance with local
codes or ordinances, these instructions, good trade practices, and
codes of country having jurisdiction.
1. Determine the best routing and termination for the vent pipe
and air inlet pipe by referring to all of the instructions and
guidelines in this Section.
2. Determine the size required for the vent pipe and air inlet
pipe.
3. Loosely assemble all venting parts without adhesive (pipe
joint cement) for correct fit before final assembly.
4. Furnace shall be installed so as to prevent the accumulation
of condensate.
5. Use of vertical piping is preferred because there will be
some moisture in the flue gases that may condense as it
leaves the vent pipe (See Instructions For Horizontal
Vents).
6. The vertical vent pipe MUST be supported so that no weight
is allowed to rest on the combustion blower.
7. Exhaust vent piping or air inlet piping diameter MUST NOT
be reduced.
8. All exhaust vent piping from the furnace to termination
MUST slope upwards. A minimum of
(304.8mm) of run is required to properly return condensate
to the furnace drain system.
9. Use DWV type long radius elbows whenever possible, as
they provide for the minimum slope on horizontal runs and
they provide less resistance in the vent system. If DWV
elbows cannot be used, use two, 45° elbows when possible.
On horizontal runs the elbows can be slightly misaligned to
provide the correct slope.
Cell
Core
Fittings Primer
Cement
Pipe
D2468
F628 & −− D2235
D2661
D2466
F891 & F656 D2564
D2665
−− F438 −−
−− −− −− D3138
1
/ " (6.4mm) per foot
4
Solv.
F493
15