Bryant 355M-40-4 ÐCOMBUSTION-AIR and Vent Pipe Termination Clearances, Location Clearance FT

TABLE 5ÐCOMBUSTION-AIR AND VENT PIPE

TERMINATION CLEARANCES

LOCATION	CLEARANCE (FT)
	U.S.A.	Canada
Above grade level or above antici-	1	1²
pated snow depth
Dryer vent	3	3
From plumbing vent stack	3	3
From any mechanical fresh air intake	1	6
For furnaces with an input capacity
less than 100,000 BtuhÐfrom any
non-mechanical air supply (windows	1	1
or doors which can be opened) or
combustion-air opening
For furnaces with an input capacity
greater than 100,000 BtuhÐfrom any
non-mechanical air supply (windows	1	3
or doors which can be opened) or
combustion-air opening
From service regulator vent, electric	4*	6³
and gas meters, and relief equipment
Above grade when adjacent to public	7	7
walkway

* Horizontal distance.

² 18 in. above roof surface in Canada.

³36 in. to electric meter in Canada only.

NOTES:

1. If installing 2 adjacent 355MAV Furnaces, refer to Multiventing and Vent Terminations section for proper vent configurations.

2. When locating combustion-air and vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the appliance's own flue products or the flue products of adjacent vents. Recirculation can cause poor combustion, inlet condensate problems, and accelerated corrosion of heat exchangers.

NOTE: Select 1 vent pipe connection and	NOTE: Select 1 vent pipe connection and
1 combustion-air pipe connection.	1 combustion-air pipe connection.

AIR
COMBUSTION- FLOW COMBUSTION-
AIR	AIR	VENT
VENT				VENT
	VENT
		COMBUSTION-	COMBUSTION-
		AIR	AIR	AIR
			FLOW
UPFLOW		DOWNFLOW
			COMBUSTION-
COMBUSTION-			AIR
AIR			VENT
VENT
AIR				AIR
FLOW				FLOW

HORIZONTAL-LEFT DISCHARGE HORIZONTAL-RIGHT DISCHARGE

A96187

Fig. 28ÐCombustion-Air and Vent Pipe Connections

NOT IN HORIZONTAL SECTION

FURNACE

PIPE DIAMETER

TRANSITION IN

VERTICAL SECTION

A93034

WARNING: 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.

WARNING: 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

Fig. 27ÐCombustion-Air and Vent Pipe Diameter

Transition Location and Elbow Configuration

CAUTION: Combustion air must not be taken from inside structure because that air is frequently contami- nated 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 prod- ucts. 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.

Ð22Ð

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 offset pipe section is recommended, as shown in Fig. 29, to reduce excessive droplets from exiting vent pipe outlet.

B.Combustion-Air and Vent Pipe Diameter

Determine combustion-air and vent pipe diameter.

1.Using Table 6, individually determine the combustion-air and vent pipe diameters. Pick the larger of these 2 pipe diameters and use this diameter for both combustion-air and vent pipes.

2.When installing vent systems of short pipe length, use the smallest allowable pipe diameter. Do not use pipe size greater than required or incomplete combustion, flame disturbance, or flame sense lockout may occur.

NOTE: Do not count elbows or pipe sections in terminations or within furnace. See shaded areas in Fig. 31, 32, 33, 34, and 35.