John Wood Direct Vent - Manuel (Page 21)

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FRESH
COMBUSTION
AIR IN
HOT
EXHAUST
GAS OUT
SCREW
Figure 15
Be sure venting is properly connected to prevent escape
of dangerous flue gases which could cause deadly
asphyxiation.
DV TERMINATION SAFETY COVER
When the heater is in operation the vent termination hood
will be hot (see Figure 15).
A Safety cover (see Figure 16) is available to prevent
accidental contact with the vent terminal. Contact your
Customer Service Department for ordering information.
Figure 16
Alternatively, a wire mesh or louvered fencing guard can
be built around the termination as shown in Figure 17.
Figure 17
VENT CONNECTIONS
After the location for the vent terminal has been selected
as outlined in Figure 6 & Figure 14, use the following
illustrations for installation:
LOCATING CLEARANCE HOLE FOR VENT
Cut a clearance hole, approximately 178mm (7”) in
diameter, through the exterior wall for the vent assembly.
The recommended height is 1.62m (64”) for 151l (40 gal.)
models, 1.85m (73”) for 189l (50 gal.) models and 1.88m
(74”) for 189l (50 gal.) Hi-Input models, as measured from
the hole center to bottom of water heater. Where the wall
is combustible and the wall thickness is over 356mm (14”),
25mm (1”) clearance to combustible surfaces around the
vent terminal is needed. The fi rst 356mm (14”) is zero
clearance (see Figure 20).
STANDARD VENT ARRANGEMENT
* If the horizontal length of the venting is less than 762mm
(30”) the restricter plate must be installed (see Figure 21,
Figure 27 thru Figure 29).
• Do not use the restricter plate in an offset installation
(see Figure 25).
• Do not use the restricter plate the horizontal length of
the venting is greater than 762mm (30”).
Note: The length of “unstretched” corrugated tube could
cause the length of the vent run to exceed the minimum. In
this case cut off a piece of the corrugated tube to achieve
the 432mm (17”) minimum vent length.