LAARS IGI-180C - Installation Manual - Manual (Page 22)

22
Vent pipes serving power vented appliances are classified by building codes as “vent connectors”.
Required clearances from combustible materials must be provided in accordance with information in this
manual under LOCATION OF WATER HEATER and CLEARANCES, and with National Fuel Gas Code
and local codes.
Venting Table – Examples of Maximum Venting Distances with Various Elbow Combinations
Maximum Straight
Pipe Distance
Number of 90 degree
elbows
Number of 45 degree
elbows
Maximum Total Equivalent
Feet (meters) of Vent Pipe
35 Ft. (10.7 m) 1 41 (12.5 m)
29 Ft. (8.8 m) 2 41 (12.5 m)
23 Ft. (7.0 m) 3 41(12.5 m)
17 Ft. (5.2 m) 4 41 (12.5 m)
33.5 Ft. (10.2 m) 1 1 41 (12.5 m)
32 Ft. (9.8 m) 1 2 41 (12.5 m)
27.5 Ft. (8.4 m) 2 1 41 (12.5 m)
NOTICE
Each 90 degree elbow is equivalent to 6 feet in straight vent pipe length. Each 45 degree elbow is
equivalent to 1.5 feet (0.46 m) in straight pipe length. The total maximum equivalent vent pipe
distance cannot exceed 41 feet (12.5 m) for horizontal venting distance. The maximum vertical height
for through the roof venting cannot exceed 21 feet (6.4 m). A condensate collector must be used if the
venting system height is more than 5 feet (1.52 m) above the water heater.
VENTING SYSTEM LAYOUT
Refer to the preceding illustration and location requirements for location of the vent terminal and also
local and state codes. In the absence of local codes, refer to the latest edition of the National Fuel Gas
Code ANSI Z223.1/NFPA 54. Keep the venting system as short as possible and keep the number of
elbows used to a minimum. The water heater may be vented directly through the wall (horizontally) or
vertically through the roof. In all cases, the maximum equivalent length of vent pipe allowed is 41
feet (12.5 m). For vertical venting, the maximum height is limited to 21 feet (6.4 m). To calculate
the total equivalent feet of vent pipe use the following formula:
D = L + (EL90 x 6) + (EL 45 x 1.5) For Length in Feet
D = L + (EL90 x 1.83) + (EL45 x 0.46) For Length in Meters
D = Total Equivalent Length of venting System
L = Length of straight section of vent/air intake pipe in feet
EL90 = Number of 90 degree elbows.
EL45 = Number of 45 degree elbows
The venting table above provides examples of maximum venting distances with various elbow
combinations.
The Everhot
® IGI model series has dedicated venting system components, which must
be ordered separately. Review the “Venting System Installation Instructions” and the venting components
in the parts list to determine the venting system layout and parts required. A Standard Vent Kit is
available for outside through the wall venting installations. The Standard Vent Kit consists of: one 90
°
discharge adapter and one horizontal vent termination kit. If this type of vent installation is not possible,
contact your supplier for additional venting components illustrated at the back of this
instruction manual.