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100221773_2000189439_Rev. 01
Important Notes and Warnings
•
This heater is certified to be installed using PVC, CPVC,
ABS or polypropylene plastic vent material. Check with
your local authorities to determine which materials
are allowed in your area. All venting material and
components must be joined with the approved primer/
cleaner and solvent cement or mechanical seals (see
“Polypropylene Vent Systems”).
•
Do not common vent this heater with any other
appliance.
•
Do not allow insulation to cover the vent piping.
•
During operation the plastic piping will expand as it
heats up and contract as it cools down. This is normal
for this type of venting. Rigidly fastening the vent piping
can cause undue stress that may result in the cracking
or fracturing the vent piping material. A fracture of the
venting pipe may pose a serious safety hazard. To
prevent stressing of the vent system, all hangers and
supports must allow the vent piping freedom to move.
•
Use long sweep elbows wherever possible. Closely-
coupled elbows and short radius elbows can reduce
the venting capacity.
•
All power vented water heaters generate a certain
amount of operational noise. In order to minimize noise
transmission to the support structure, use isolation pads
between the pipe hangers and the vent pipe.
•
Most power vent installations develop some
condensation in the vent piping. When using long runs
of venting or when the venting passes through cold or
unheated areas, considerable amounts of condensate
from the flue gases can develop. Provision must be
made for the condensate to drain freely from the
system or to be collected in a condensate trap(s) that
can be drained. Damage or fracture of the vent piping
may occur if the condensate is allowed to collect and
freeze. Pooling of condensate can restrict airflow and
can cause nuisance failures of the system.
•
In regions that experience freezing conditions, slope the
venting back towards the heater so that the condensate
will drain back to the blower and be collected in the
condensate trap. Draining condensate out through the
termination can result in vent freeze up resulting in a
nuisance shut down situation. Ice formed from frozen
condensate can cause a safety hazard. See also notes
in the “Venting” section.
Venting terminations and sizing
•
Heaters are supplied with a 3”x3” rubber coupling to
attach the venting to the blower and a 3”, 45° vent
termination elbow.
•
Supplied with this heater are several vent termination
screens (see Figure 32).
Installed in the vent termination elbow, the vent screen
is required to keep foreign objects, rodents and small
birds from entering the venting system. These screens
have been sized to ensure maximum energy efficiency of
the vent system based on the “equivalent length” of the
vent piping. CHOOSE ONLY the ONE SCREEN THAT
MATCHES YOUR VENTING CONFIGURATION (see
Figure 32). How to determine the “equivalent length” is
shown in Figure 33 and in Table 2.
Vent screen installation
Note: The correct vent screen is required for proper
operation of this water heater. Failure to install and secure
the correct screen can result in improper vent operation
which can result in the water heater overheating or
nuisance shut downs.
•
Install the appropriate vent screen into the vent
termination elbow.
•
Gently push the screen into the termination elbow until
it sits against the inside shoulder.
•
The metal wire screens are self-securing.
•
Plastic screens must be secured with (2) screws:
1. Install plastic screen into elbow (see Figure 32).
2. Orient screen as shown in see Figure 32 with an
opening at the bottom of the assembly and the
smooth side facing in.
3. Ensure screen is fully seated against shoulder in
elbow.
4. Secure screen in place with screws (field supplied)
(see Figure 32).
with 3 in. venting (short)
with 3 in. venting (long)
VENT LENGTH LESS THAN OR
EQUAL TO 20 EQUIVALENT FT. USE
THIS SCREEN (SUPPLIED).
VENT LENGTH GREATER THAN
20 EQUIVALENT FT.
USE THIS SCREEN (SUPPLIED).
with 4 in. venting
VENT LENGTH GREATER THAN
50 EQUIVALENT FT. USE THIS
SCREEN (SUPPLIED).
ELBOW
#6 SHEET METAL
SCREW (FIELD
SUPPLIED)
PLASTIC
SCREEN
SHOULDER
OPEN
CLOSED
POCKET
POCKETS
FACING OUT
Figure 32.
