Venting Requirements
Approved Materials
Approved vent and intake air pipe materials that may be used in the United States:
•PVC Schedule 40 (ASTM D 2241 / CSA B181.2, ASTM D 1785 / CSA B137.3
•CPVC Schedule 40 (ASTM
•ABS (ASTM
Approved vent and intake air pipe materials that must be used in Canada:
•ULC S636 PVC / CPVC
Field Supplied Fittings
Field supplied fittings should be equivalent to the piping material being installed. Field installed/supplied fittings will add equivalent feet to the vent or intake air piping as indicated below. All field supplied/installed fittings and piping must be factored into the equivalent feet calculations.
•90° elbows (short or long radius) are equivalent to 5 linear feet (152 cm) of pipe.
•45° elbows (short or long radius) are equivalent to 2.5 linear feet (76 cm) of pipe.
Primer and Cement
Tetrahydrofuran (THF) primer should be used to prepare the surfaces of pipe and fittings for solvent welding. If CPVC or ABS pipe and fittings are used, then the proper cement must be used for all joints, including joining the pipe to the factory provided terminations (PVC material). PVC Materials should use ASTM
Pipe Size Requirements
The water heaters covered in this manual are certified for the use of 4 and 6 inch pipe for the vent (exhaust) and intake air piping. If the installed equivalent length for the intake air or vent piping will be 70 feet (21.3 m) or less, 4 inch pipe must be used. If the installed equivalent length will be more than 70 feet (21.3 m), 6 inch pipe must be used.
Note: Install the pipe size required for the installed equivalent
length of each pipe independently. IE: If the intake air pipe will be 70 equivalent feet or less and the vent pipe will more than 70 equivalent feet; the intake air pipe must be installed using 4 inch pipe and the vent must be installed using 6 inch pipe.
Maximum Equivalent Lengths
Four Inch Pipe
The water heaters covered in this manual are certified to a maximum length of 4 inch pipe for the exhaust venting arrangement of 70 equivalent feet (21.3 m). The certified maximum length of 4 inch pipe for intake air piping is also 70 equivalent feet (21.3 m). IE: On Direct Vent installations both pipes can be up to 70 equivalent feet (21.3 m).
Six Inch Pipe
The water heaters covered in this manual are certified to a maximum length of 6 inch pipe for the exhaust venting arrangement of 120 equivalent feet (36.5 m). The certified maximum length of 6 inch pipe for intake air piping is also 120 equivalent feet (36.5 m). IE: On Direct Vent installations both pipes can be up to 120 equivalent feet (36.5 m).
Intake Air and Vent Pipe Clearances
The minimum clearance from combustible materials for the vent (exhaust) and intake air piping shall be 0 inches. Vent or intake air piping passing through a combustible wall or ceiling must be a continuous run (no joints).
Minimum Equivalent Lengths
Four Inch Pipe
The water heaters covered in this manual are certified to a minimum length of 4 inch pipe for the vent (exhaust) of 15 equivalent feet (4.6 m). There is no minimum equivalent feet requirement for the intake air pipe.
Six Inch Pipe
The water heaters covered in this manual are certified to a minimum length of 6 inch pipe for the vent (exhaust) of 70 equivalent feet (21.3 m). There is no minimum equivalent feet requirement for the intake air pipe.
Maximum Number Of Elbows
The vent pipe may have a maximum of six 90° elbows installed. The intake air pipe may have a maximum of six 90° elbows installed. IE: in a Direct Vent configuration each pipe can have up to six (6) 90° elbows installed. Two (2) 45° elbows equal one (1) 90° elbow. Each 90° elbow is equivalent to 5 feet (1.5 m) of linear pipe, 45° elbows are equivalent to 2.5 feet (0.75 m) of linear pipe.
Factory Supplied Fittings
The water heater ships with two (2) factory supplied 4 inch terminations (PVC 45° elbows with debris screen). Factory supplied vent and intake air terminations or concentric terminations must be used. Factory supplied terminations and installed fittings (exhaust elbow and intake air connection) add zero equivalent feet to the vent and intake air piping.
Table 7
Number of | 4 Inch Pipe | 6 Inch Pipe | |
90° Elbows |
|
| |
Maximum Feet (Meters) | Maximum Feet (Meters) | ||
Installed | |||
|
| ||
One (1) | 65 feet (19.8 meters) | 115 feet (35.0 meters) | |
Two (2) | 60 feet (18.2 meters) | 110 feet (33.5 meters) | |
Three (3) | 55 feet (16.8 meters) | 105 feet (32.0 meters) | |
Four (4) | 50 feet (15.2 meters) | 100 feet (30.5 meters) | |
|
|
| |
Five (5) | 45 feet (13.7 meters) | 95 feet (29.0 meters) | |
Six (6) | 40 feet (12.2 meters) | 90 feet (27.4 meters) |
6 Inch Extended Vent Terminations
When 6 inch intake air or vent pipe is installed using standard terminations, factory supplied 6 inch terminations must be used. Contact your local distributor or call the parts department (phone number listed on the back cover of this manual) to order 6 inch termination(s).
Optional Concentric Terminations
(A)HCG3 130T 300 models installed using 4 inch vent/intake air piping use the 4 inch concentric termination. (A)HCG3 130T 300 models installed using 6 inch vent/intake air piping use the 6 inch concentric termination. (A)HCG3 130T 400 models must use the 6 inch concentric termination on all installations.
Contact your local distributor or call the parts department phone number listed on the back cover of this manual to order.
•4” Concentric Termination Part # 9006328005
•6” Concentric Termination Part # 9006144005
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