A.O. Smith THR-160 Installation Instructions And Use & Care Manual Download

Page: 23 / 72

Installing the Vent Pipe.

WARNING! Improper installa on

can cause nausea or asphyxia on,
severe injury or death from carbon
monoxide and

ue gases poisoning.

Improper installa on will void
product warranty

• When inser ng the pipe into the

exhaust/intake port, make sure
that the pipe end is cut straight and
posi oned properly under the o-ring
to seal the connec on

rmly.

• Improper ven ng of this appliance

can result in excessive levels of
carbon monoxide which can result in
severe personal injury or death.

Vent Piping

Insert 2" straight pipe fully
into the exhaust/intake ports.
(See Figure 15) The pipes

should insert 2 inches.

WARNING: The exhaust vent pipe

connec on to the water heater must
be

ush to maintain a proper seal.

Check pipe for a 90° edge before
installa on. DO NOT use a

eld cut

end for the connec on. Failure to
follow can cause carbon monoxide
poisoning or death.

NOTICE:

For 3” Ven ng, install a 2” x

3” increaser to convert to 3” ven  ng.
For low clearance installa  ons, a 2”
long sweep elbow may be used. Then
1    max length straight pipe may be
used to

t a 2” x 3” increaser.

Air Intake for Power Vent Installs:
Insert the male end of a 2” or 3” long
sweep street elbow into the heater’s
air intake port.

Use a screwdriver to tighten
the clamp. (See Figure 15)

Use the supplied self-tapping
screws to secure the venting
to the intake and exhaust

ports as shown in the image on the
right. (See Figure 15)

Power Vent (PV)

Direct Vent (DV)

3” Pipe

2” to 3”
Adapter

2” Pipe

3” Pipe

2” to 3”
Adapter

2” Pipe

Pipe end

ŶŽƚŇƵƐŚ
ǁŝƚŚďĂƐĞ͘

Pipe end

ŝƐŇƵƐŚ
ǁŝƚŚďĂƐĞ͘

Not a
90° edge

ǆŚĂƵƐƚsĞŶƚ

Pipe

90° edge

ǆŚĂƵƐƚsĞŶƚ

Pipe

ǆŚĂƵƐƚ

Intake

Port

Intake Port

ǆŚĂƵƐƚ

Port

Clamp

Self-Tapping Screw

Figure 15 -

Vent Pipe Installa on

Exhaust Vent for

Indoor Installa on

ABS, PVC, CPVC or
polypropylene vent

The Indoor model can be vented with
ABS, PVC, CPVC, or polypropylene
(temperature rated up to 149°F).
In Canada, plas c ven ng must be
cer

ed to ULC S636.

• The maximum length of exhaust

ven ng and intake piping shall not
exceed the lengths listed in Table 8.

• Do not use more than 5 elbows in a

vent system. 90 degree elbow add-
ed, deduct 5 . 45 degree elbows
count as 2.5 feet. If an elbow(s)
is used in the vent system, deduct
each equivalent length from the
Max. vent length to decide the total
vent length.

• When the horizontal vent run

exceeds 5 (1.5 m), support the
vent run at 3 (0.9 m) intervals with
overhead hangers.

• In areas of high rainfall the installa-

on of the rain trap may be neces-

sary.

• Slope horizontal ven ng sec ons

1/4" upwards for every 12" (305
mm) toward the termina  on or
according to local and state codes,
or in the absence of local or state/
provincial codes, the current edi  on
of the ANSI Z223.1/NFPA 54, Na  on-
al Fuel Gas Code or B149.1, Natural
gas and propane installa  on code.

Residen al Gas Tankless Water Heater Use and Care Guide • 23

INSTALLATION