Venting terminations and sizing
•
Refer to Figure 33 and Table 2 for vent pipe materials
and sizing. Examples of the vent terminations are
shown in Figure 34 & Figure 35. If the installation
requires a vent riser, suitable drainage must be
provided to ensure condensation does not accumulate.
Termination through a roof is shown Figure 36.
•
40, 50 and 60 gallon heaters with rated inputs of 50k
Btu/hr or less are supplied with a 2”-3” rubber coupling
to attach the venting to the blower and a 2”, 45° vent
termination elbow.
with 2 in. venting (short)
with 2 in. venting (long)
For heaters with rated inputs of 50k Btu/hr or less:
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
125 EQUIVALENT FT.
USE THIS SCREEN (SUPPLIED).
with 3 in. venting
VENT LENGTH GREATER THAN
50 EQUIVALENT FT.
USE THIS SCREEN (SUPPLIED).
with 3 in. venting
VENT LENGTH LESS THAN OR
EQUAL TO 50 EQUIVALENT FT.
USE THIS SCREEN (SUPPLIED).
Figure 31.
•
50 and 75 gallon heaters with a rated input of 60k Btu/
hr or more are supplied with a 3”-3” 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 31 & 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 ef
fi
ciency 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 31 & Figure 32). How to determine the “equivalent
length” is shown in Figure 33 and in Table 2.
Vent screen installation
•
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) drops of
silicone sealant. This will allow for easy removal for
inspection and cleaning.
with 4 in. venting
VENT LENGTH GREATER THAN
50 EQUIVALENT FT.
USE THIS SCREEN
(SUPPLIED).
with 3 in. venting (short)
with 3 in. venting (long)
For heaters with rated inputs of 60k Btu/hr or more:
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).
Figure 32.
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