Payne PG9MAA, Installation Manual

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5. Disassemble loose pipe fittings. Clean and cement using same procedures as used for system piping.
6. Check required dimensions as shown in Fig. 41 or 42.
D. Multiventing and Vent Terminations
When 2 or more PG9MAA Furnaces are vented near each other, each furnace must be individually vented. NEVER common vent or breach vent
PG9MAA furnaces. When 2 or more PG9MAA furnaces are vented near each other, 2 vent terminations may be installed as shown in Fig. 45,
46, 47, 48, and 49 , but next vent termination must be at least 36 in. away from first 2 terminations. It is important that vent terminations be made
as shown to avoid recirculation of flue gases. Dimension "A" in Fig. 45, 46, 47, 48, and 49 represents distance between pipes or rain shields, as
touching or 2-in. maximum separation.
PROCEDURE 8—NON-DIRECT VENTING (SIZES 040 THROUGH 120 ONLY)
A. General
The PG9MAA can be vented as either a direct vent or as a non-direct vent application. This section describes non-direct venting applications only.
For direct vent applications, refer to the Direct Venting section.
NOTE:
The 140 Size unit may not be installed in non-direct vent applications.
Non-direct venting applications require a dedicated, (one PG9MAA furnace only) sealed vent system. All air for combustion is taken from the area
adjacent to furnace, and all flue products are discharged to outdoor atmosphere.
B. Combustion-Air and Vent Piping
GENERAL
WARNING: FIRE AND EXPLOSION HAZARD
Failure to follow this warning could result in fire, property damage, personal injury, or death.
Solvent cements are combustible. Keep away from heat, sparks, and open flame. Use only in well-ventilated areas. Avoid breathing
in vapor or allowing contact with skin or eyes.
Combustion-air and vent pipe, fittings, primers, and solvents must conform to American National Standards Institute (ANSI) standards and
American Society for Testing and Materials (ASTM) standards. See Table 6 for approved materials for use in the U.S.A. and Canada. In Canada
construct all combustion-air and vent pipes for this unit of CSA or ULC schedule-40 PVC, PVC-DWV or ABS-DWV pipe and pipe cement. SDR
pipe is NOT approved in Canada.
Vent pipe termination must be installed with adequate clearances to building openings and equipment to comply with national and local codes.
See Table 13 for required clearances.
COMBUSTION AIR PIPE
CAUTION: UNIT CORROSION HAZARD
Excessive exposure to contaminated combustion air may result in safety and performance related problems.
Combustion air must not be taken from inside a structure that is frequently contaminated by halogens, which include fluorides,
chlorides, bromides, and iodides. These elements are found in aerosols, detergents, bleaches, cleaning solvents, salts, air fresheners,
adhesives, paint, and other household products. Locate combustion-air inlet as far as possible from swimming pool and swimming pool
pump house.
NOTE: Furnace combustion-air connections are sized for 2-in. pipe. The combustion-air pipe will be 2-in. diameter in all installations.
Furnace combustion-air connection must be attached as shown in Fig. 50. Combustion-air intake housing plug may need to be relocated in some
applications.
Combustion-air pipe must terminate outside of furnace casing with 1 elbow. Orient elbow so that opening faces down for upflow or downflow
applications. Orient elbow so that it faces sideways (left or right) for horizontal left or horizontal right applications. (See Fig. 50.) Maintain a 3-in.
minimum clearance between the opening of the combustion-air inlet pipe and any object.
NOTE:
All pipe joints must be watertight except attachment of combustion-air inlet pipe to inlet housing connection, since it may be necessary
to remove pipe for servicing.
Install combustion air inlet pipe as follows:
1. Assemble combustion-air inlet pipe.
a. Permanently install perforated disk assembly (factory-supplied in loose parts bag) in combustion-air elbow using RTV or by cementing.
(See Fig. 51.)
For 120 size units only: Separate the 2 halves of perforated disk assembly and use only the shouldered disk half.
b. Determine length of straight portion of combustion-air inlet pipe from table in Fig. 51.
c. Cut field-supplied 2-in diameter PVC pipe to determined length.
d. Permanently attach elbow/perforated disk assembly to straight portion of pipe using RTV or by cementing. (See Fig. 51.)
2. Attach combustion-air inlet pipe(s).
a. Determine location of combustion-air intake pipe connection to combustion-air intake housing as shown in Fig. 50 for application.
b. Reposition combustion-air intake housing plug fitting in appropriate unused intake housing connection.
c. Install pipe support (factory-supplied in loose parts bag) into selected furnace casing combustion-air pipe hole. Pipe support should be
positioned at bottom of casing hole.
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