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, as well as the National Fuel Gas Code and local codes.

Table 7. Venting Table - Examples of Maximum Venting Distances.

Maximum Straight

Number of 90º Elbows

Maximum Total Equivalent

Pipe Distance

Length of Vent Pipe

 

41 ft (12.5 m)

0

41 ft (12.5 m)

35 ft (10.7 m)

1

41 ft (12.5 m)

29 ft (8.8 m)

2

41 ft (12.5 m)

23 ft (7.0 m)

3

41 ft (12.5 m)

17 ft (5.2 m)

4

41 ft (12.5 m)

11 ft (3.4 m)

5

41 ft (12.5 m)

5 ft (1.5 m)

6

41 ft (12.5 m)

NOTICE

Each 90º elbow is equivalent to 6 ft (1.8 m) in straight vent pipe length. Each 45 degree elbow is equivalent to 3 ft (0.9 m) in straight pipe length. The total maximum equivalent vent pipe distance cannot exceed 41 feet (12.5 m).

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 (latest edition) or Canadian Installation Codes CAN/CGA-B149 (latest edition). 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). To calculate the total equivalent feet of vent pipe use the following formula:

D = L + (EL90 x 6) + (EL 45 x 3)

For Length in Feet

D = L + (EL90 x 1.8) + (EL45 x 0.9)

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 90º Elbows.

EL45 = Number of 45º Elbows

The venting table above provides examples of maximum venting distances with various elbow combinations.

The Bradford White EverHot® TGHE model series has dedicated venting system components, which must be ordered separately. Review the “Venting System Installation Instructions” and the venting components later in this manual 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 a venting supplier listed in this manual for additional venting components illustrated at the back of this instruction manual.

VENTING SYSTEM INSTALLATION

Reference the preceding section and venting components illustrations at the end of this manual to determine the parts required for your particular venting system installation. The required venting component parts are available from the suppliers listed in this manual. Use the Venting System Installation Instructions supplied with the venting components for detailed instructions on putting together the venting components.

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Bradford-White Corp TGHE-1991-N(X), TGHE-160I-N(X) instruction manual Venting System Layout, Venting System Installation