Enviro 6G50100 series Instruction Manual Download Page 20

Page: 20 / 112

ventInG

Never operate the water heater unless it is vented to the outdoors.
The instructions in this section of the manual must be followed

to avoid choked combustion or recirculation of flue gases. Such

conditions cause sooting of the combustion chamber, burners and

flue tubes and creates a risk of asphyxiation.

INTAKE VENT TERMINAL

BACKFLOW PREVENTER

fIGure 13.

bacKflow preventer

For direct vent application where combustion air might be supplied

from extremely cold ambient through fresh air intake piping system,

it is recommended that a backflow preventer be installed at the

intake vent terminal close to the blower following the following

procedure, before proceeding with installation of the rest of the

fresh air intake piping. See Figure 13. The installation of the

Backflow Preventer doesn’t affect the maximum equivalent vent

length specified in subsequent sections.

Prepare a 2” PVC pipe of 2” long (field supplied).

Glue 1” long segment of above PVC pipe into the backflow

preventer at the end the embossed arrow mark points at. Please

note that the arrow mark is not only for air flow direction but also

for orientation. The backflow preventer is configured so that

when one faces the arrow mark pointing from left to right, the

spring inside is on the top.

Remove the air intake screen from the intake vent terminal on

the unit.

Glue the assembly in Step 2 into the intake vent terminal so that

the backflow preventer butts with the intake vent terminal and

so that if one views from the entrance of backflow preventer, the

arrow mark is at 2 o’clock location.

If no additional fresh air intake piping will be installed, install the

wire screen in Step 3 into the backflow preventer entrance.

vent pIpe terMInatIon

The first step is to determine where the vent pipe will terminate.

See Figures 15, 16, 17 and 18. The vent may terminate through a

sidewall as shown in Figures 15 and 16 or through the roof as shown

in Figures 17 and 18.
The vent system must terminate so that proper clearances are

maintained as cited in local codes or the current edition of the

Natural Gas and Propane Installation Code (CAN/CSA-B149.1).

See Figures 13 and 14.
Instructions on proper installation through a sidewall are provided

in Figures 15A, 15B, 15C, and 16.
Plan the vent system layout so that proper clearances are maintained

from plumbing and wiring.
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

FACTS TO CONSIDER ABOUT

LOCATION

and INSTALLING THE WATER HEATER, and with the

Natural Gas and Propane Installation Code and local codes.

plannInG the vent sYsteM

Plan the route of the vent system from the exhaust elbow to the

planned location of the vent terminal.
1. Layout total vent system to use a minimum of vent pipe and elbows.
2. This water heater is capable of venting flue gases equivalent to

45’ (13.7 m) of 2” pipe, 128’ (39 m) of 3” pipe as listed in Table 5.

table 5

number of

90° elbows

2” Maximum

pipe - ft. (m)

3” Maximum

pipe - ft. (m)

40 (12.19)

120 (36.57)

35 (10.66)

115 (35.05)

30 (9.14)

110 (33.52)

25 (7.62)

105 (32)

20 (6.09)

100 (30.48)

15 (4.57)

95 (28.95)

The minimum vent length for each pipe size is one 90° plus 2’

(61 cm) of straight pipe and the appropriate termination.

note:

The equivalent feet (m) of pipe listed above are

exclusive of the termination. That is, the termination, with

an installed screen, is assumed to be in the system and

the remainder of the system must not exceed the lengths

discussed above.

3. The exhaust elbow assembly is designed to accept only

straight sections of 2” pipe. To start, a minimum 2” (5.1cm)

maximum 6” long of 2” pipe must be inserted and glued to the

exhaust elbow assembly if utilizing 3” vent pipe. Use the same

method with the blower inlet if a direct vent configuration is

utilized.

If using 2” inch vent pipe:

A minimum of 2” (5.1cm) diameter vent pipe must be attached

to the exhaust elbow assembly. The total system cannot

exceed the lengths discussed above, where each elbow is

equal to 5 equivalent feet (1.5m) of straight pipe.

If using 3” inch vent pipe:

Two inches (5.1cm) of 2” pipe must be attached to the exhaust

elbow assembly before adding a reducer to acquire the
desired pipe diameter. An appropriately sized 45 degree elbow
(supplied locally-a schedule 40 DWV) vent terminal must
be obtained with an equivalent screen (supplied in vent kit).
The total system cannot exceed the equivalent pipe lengths
discussed above where each elbow is equal to 5 feet (1.5m)
of straight pipe (3” vent pipe).