Lochinvar WH 55-399 Installation & Operation Manual page 30

5
Vertical direct venting
Vertical termination – optional concentric vent
Do not operate the appliance with
WARNING
the rain cap removed or recirculation
of combustion products may occur.
Water may also collect inside the larger
combustion air pipe and flow to the
burner enclosure. Failure to follow this
warning could result in product damage
or improper operation, personal injury,
or death.
4. Install the Y concentric fitting pipe assembly through the
structure's hole and field supplied roof boot/flashing.
Do not allow insulation or other materials
NOTICE
to accumulate inside the pipe assembly
when installing through the hole.
5. Secure the assembly to the roof structure as shown
below in FIG. 5-6 using field supplied metal strapping or
equivalent support material.
Figure 5-6 Concentric Vent Roof Installation
Ensure termination height is above the
NOTICE
roof surface or anticipated snow level (12
inches in U.S.A. or 18 inches in Canada) as
shown in FIG. 5-4, page 29.
If assembly is too short to meet height
NOTICE
requirement, the two (2) pipes supplied
in the kit may be replaced by using the
same diameter, field supplied SDR-26 PVC
(D2241) pipe. Add standard schedule 40
PVC pipe for #CVK3007 Do not extend
dimension D more than 60 inches (see FIG.
4-9 and FIG. 4-10, page 25).
30
Installation & Operation Manual
DO NOT use field-supplied couplings to
CAUTION
extend pipes. Airflow restriction will occur.
6. Install the rain cap and the small diameter pipe assembly
into the roof penetration assembly.
diameter pipe is cemented and bottomed in the Y concentric
fitting.
7. Cement the appliance combustion air and vent pipes to
the concentric vent termination assembly. See FIG. 5-6 for
proper pipe attachment.
8. Operate the appliance through one (1) heat cycle to ensure
combustion air and vent pipes are properly connected to
the concentric vent termination connections.
Multiventing vertical terminations
When two (2) or more direct vent appliances are vented near
each other, each appliance must be individually vented (see
FIG. 5-7). NEVER common vent or breach vent this appliance.
When two (2) or more direct vent appliances are vented near
each other, two (2) vent terminations may be installed as shown
in FIG. 5-7. It is important that vent terminations be made as
shown to avoid recirculation of flue gases.
Figure 5-7 Concentric Vent and Combustion Air Vertical
Termination
12" (18" FOR CANADA)
MINIMUM CLEARANCE
ABOVE HIGHEST
ANTICIPATED SNOW
LEVEL. MAXIMUM OF
24" ABOVE ROOF.
Ensure the small
12"
MINIMUM
COMBUSTION
AIR (TYPICAL)