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Combustible Air Supplied by Mechanical
fan or Make up air device.
The T-H1 appliance is equipped with a
combustible air sensor that will shut off the unit
when inadequate combustible air supply to unit
is detected.
If a mechanical fan or make up air device is
used to supply air to the appliance or utility
room, the installer should make sure it does
not create drafts which could cause nuisance
shutdowns. If a blower is necessary to provide
adequate combustion air to the appliance, a
switch or equivalent device must be wired
(interlocked) with the appliance control circuit
or other proper devices to prevent the
appliance from firing unless the blower is
operating.
Direct intake vent system
This T-H1 appliance may be converted to a
direct vent (sealed combustion) appliance by
installing an adapter (part No TK-TV07) which
will bring all required combustible air from
outside the building. The T-H1 must be
installed in a location where the proper amount
of combustible air will be available to it at all
times without obstructions. If used as a direct
vent appliance, the T-H1 requires a 3”
combustible air supply pipe. The intake pipe
must be sealed airtight with aluminum tape and
can be made of ABS, galvanized steel,
corrugated aluminum, corrugated stainless
steel or Category III stainless steel.
Ensure that the unit is set for direct vent and
indoor installation. The ‘DIRE’ dipswitch on the
computer board should be switched to its ‘ON’
(up) position and the ‘OUT’ dipswitch should
be switched to its ‘OFF’ (down) position:
Direct vent dip switch settings
VENTING INSTRUCTIONS
General
WARNING:
Improper venting of this appliance
can result in excessive levels of carbon
monoxide which can result in severe personal
injury or death.
This appliance must be vented in accordance
with the section “Venting of Equipment" of the
latest edition of the Natural Fuel Gas Code,
ANSI Z223.1 and all applicable local building
codes. In Canada, follow section 7 of the
CAN/CSA B149.1 Natural Gas and Propane
Installation Code.
Exhaust Vent
This is a Category III appliance and must be
vented accordingly. The vent system must be
sealed air tight. All seams and joints must be
sealed with high heat resistant silicone sealant
or UL listed aluminum adhesive tape having a
minimum temperature rating of 350ºF. For best
results, a vent system should be as short and
straight as possible.
This unit requires 4”, Category III approved,
single wall stainless steel vent pipe or any
other Category III approved, non-combustible,
corrosion-resistant material. The following are
UL listed manufacturers: ProTech Systems Inc.
(FasNSeal), Flex-L Inc., Z-Flex Inc. (Z-Vent III)
and Heat-Fab Inc. (Saf-T Vent).
Follow the
vent pipe manufacturer’s instructions when
installing the vent pipe.
Do not common vent
this appliance with any other vented appliance.
The maximum length of exhaust vent piping
must not exceed 50 ft. deducting 5 ft. for each
elbow used in the venting system. Do not use
more than 5 elbows.
Pipe
Diam
eter
Max. #
of
Elbows
Maximum Vertical or
Horizontal Vent Length
4” 5
50
ft
For each elbow added, deduct 5 ft. from
maximum vent length:
# of Elbows
Max. Vertical or
Horizontal Length
0 50
ft.
1 45
ft.
2 40
ft.
5 25
ft.
4” exhaust
3” intake
