John Wood Takagi - 320H-520H - Manual (Page 8)

8
520H Model Installation
The 520H models are equipped with a thermistor and hi-limit
switch for the exhaust gas, detecting excess temperatures
within the flue and enabling the unit to safely stop opera-
tions if needed. These components are always monitoring
exhaust gas conditions in order to prevent heat damage to
PVC (Plastic) venting if PVC is used.
If the exhaust gas temperature exceeds 60°C (140°F), these
components will enable the unit to safely stop operations.
520H model requires a 102mm (4 in.) make-up intake air
supply pipe. The intake pipe must be sealed airtight.
Air supply pipe can be made of ABS, PVC, galvanized
steel, corrugated stainless steel, or Category lll / IV stain-
less steel.
In any areas subject to freezing temperatures, the manu-
facturer highly recommends an indoor installation with
the 520H model. In such an installation, freezing issues
can only occur if cold air enters through the venting into
the heat exchanger, whether by negative pressures
within the installation location or by strong outside winds.
It is the installer’s responsibility to be aware of these
issues and take all preventative measures. The manu-
facturer will not be responsible for any damage to the
heat exchanger as a result of freezing. The warranty will
not be covered if the heat exchanger is damaged due to
freezing. Refer to the section on the Freeze Protection
System on pg. 29 for more information.
Sidewall venting is recommended for the 520H models.
Vertical venting (roof termination) is acceptable.
The manufacturer recommends running the exhaust
vent and the intake pipe as parallel as possible.
The PVC adaptor is used to make the connection
between the 520H vent collar and PVC vent pipe easier
and for maintenance purposes.
Maintain Clearances.
Bottom 305mm
(12 in.)
Side
76mm
(3 in.) Back
13mm
(0.5 in.)
Front 76mm
(4 in.) (610mm
(24 in.)
Recommended
for
Maintenance)
Top 305mm
(12 in.)
Side
76mm
(3 in.)
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Venting Instructions
General
WARNING
Improper venting of this appliance can
result in excessive levels of carbon mon-
oxide which can result in severe personal
injury or death.
The 520H models must be vented in accordance with
the section “Venting of Equipment" of the latest edition of
Section 7 of the CSA B149.1 Natural Gas and Propane
Installation Code as well as applicable local building
codes.
When installing the vent system, all appli-
cable national and local codes must be
followed. If you install thimbles, fire stops
or other protective devices and they pen-
etrate any combustible or noncombustible
construction, be sure to follow all appli-
cable national and local codes.
The use of venting materials approved for Category III/IV
appliances is recommended whenever possible. However,
520H may also be vented with plastic pipe materials such
as PVC. For details, please refer to the Exhaust vent (PVC
vent) section below. Vent installations which utilize plastic
vent systems must use venting that complies with ULC
S636.
Exhaust vent (PVC vent)
The 520H models can be connected with PVC venting certi-
fied to ULC S636 standards.
The maximum length of exhaust vent piping must not
exceed 15.24m (50 ft.) for 102mm (4 in.) venting and
7.6m (25 ft.) for 76mm (3 in.) venting (deducting 5 ft. for
each elbow used in the venting system). Do not use more
than 5 elbows for 102mm (4 in.) venting and 2 elbows for
76mm (3 in.) venting.
When the horizontal vent run exceeds 1.5m (5 ft.), sup-
port the vent run at 915mm (3 ft.) intervals with overhead
hangers. •
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