4
Servicing should only be performed by a Qualified Service Agent
venting
This section of the Service Manual is not a complete venting installation instruction. Refer to the Instruction
Manual that came with the water heater; ensure the venting has been installed per all Instruction Manual
requirements. Costs to correct installation errors are not covered under the limited warranty.
general venting information
The water heaters covered in this manual are operationally equivalent to Category IV appliances and may be
installed in either a Power Vent or direct Vent configuration.
Category iv appliance
Category IV appliances operate with a positive vent (exhaust) static pressure and with vent gas temperatures
low enough to produce condensate in the vent piping.
Power Vent Configuration
Power Vent configurations derive all combustion air from the room where they are installed and discharge all
flue gases to the outdoor atmosphere through a sealed vent (exhaust) pipe. Power vent configurations have
one vent pipe connected to the water heater which can be terminated in a vertical or horizontal arrangement.
Direct Vent Configuration
direct Vent configurations derive all combustion air directly from the outdoor atmosphere through a sealed
intake air pipe and discharge all flue gases to the outdoor atmosphere through a sealed vent (exhaust) pipe.
direct Vent configurations have two pipes connected to the water heater, one vent pipe and one intake air
pipe. direct Vent configurations can also be terminated in a vertical or horizontal arrangement.
maXimum eQuivalent length reQuirements
The the intake air and/or vent pipe for the water heaters covered in
this manual can be installed using 2 inch or 3 inch pipe depending
on the overall “equivalent length" of each pipe. Equivalent lengths
are calculated by adding the total linear feet of installed pipe to the
accumulated equivalent length of all field installed elbows.
Each 2 inch or 3 inch 90° elbow installed is equivalent to 5 linear
feet of pipe. 45° elbows are equivalent to 2.5 linear feet of pipe.
on direct Vent installations the intake air and/or vent pipe are calculated separately and each pipe's total
equivalent length must not exceed the maximum equivalent length requirements stated in the Instruction
Manual that came with the water heater, see Table 1 below.
table 1
†Number of 90° Elbows
Installed
2 inch pipe
3 inch pipe
Maximum Feet (Meters)
Maximum Feet (Meters)
one (1)
40 feet (12.2 meters)
120 feet (36.6 meters)
Two (1)
35 feet (10.7 meters)
115 feet (35.0 meters)
Three (3)
30 feet (9.1 meters)
110 feet (33.5 meters)
Four (4)
25 feet (7.6 meters)
105 feet (32.0 meters)
Five (5)
20 feet (6.1 meters)
100 feet (30.5 meters)
Six (6)
15 feet (4.6 meters)
95 feet (29.0 meters)
† Two 45° elbows are equivalent to one 90° elbow.
pipe siZe reQuirements
Ensure the correct size pipe has been used for the length of intake air and/or vent piping installed. 2 inch pipe
may be used up to 40 equivalent feet with one 90° elbow installed, if the installation requires more equivalent
feet of intake air and/or vent pipe, 3 inch pipe must be used up to the maximum shown in Table 1 above.
maXimum elbow reQuirements
The maximum number of 90° elbows allowed for the vent pipe is six (6). on direct Vent installations the
maximum number of 90° elbows allowed for the intake air pipe is six (6), see Table 1 above.
2”
3”
= 5 linear feet of pipe
= 5 linear feet of pipe
