Carrier 58MVP Installation, Start-Up, And Operating Instructions Manual page 22

When vent pipe is exposed to temperatures below freezing,
such as when it passes through an unheated space or when a
chimney is used as a raceway, pipe must be insulated as
shown in Table 6 with Armaflex-type insulation.
Combustion air must not be taken from inside structure
because that air 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.
Excessive exposure to contaminated combustion air will
result in safety and performance related problems.
VENT PIPE
HORIZONTAL TO ROOF
COMBUSTION-AIR PIPE
VERTICAL TO ROOF
12" MIN
COMBUSTION-AIR PIPE
12" MIN
NOTE: A 12-in. minimum horizontal pipe section is recommended with
short (5 to 8 ft) vent systems. This recommendation is to reduce
excessive condensate droplets from exiting the vent pipe.
Fig. 29—Short Vent (5 to 8 Ft) System
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. Failure to follow this warning could result in fire,
property damage, personal injury, or death.
All combustion-air and vent pipes must be airtight and
watertight. Pipes must also terminate exactly as shown in Fig.
31, 32, 33, 34, or 35. Failure to follow this warning could
result in property damage, personal injury, or death.
NOTE: The minimum combustion-air and vent pipe length (each)
for these furnaces is 5 ft. Short pipe lengths (5-8 ft) may discharge
water droplets. These droplets may be undesirable, and a 12-in.
minimum horizontal pipe section is recommended, as shown in
Fig. 29, to reduce excessive droplets from exiting vent pipe outlet.
COMBUSTION-AIR AND VENT PIPE DIAMETER
Determine combustion-air and vent pipe diameter.
1. Using Table 5, determine preliminary combustion-air pipe
diameter.
2. Using Table 5, determine preliminary vent pipe diameter.
VENT PIPE
HORIZONTAL TO SIDEWALL
COMBUSTION-AIR PIPE
VENT PIPE
VERTICAL TO SIDEWALL
22
12" MIN
COMBUSTION-AIR PIPE
12" MIN
VENT PIPE
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