Venting Terminations and Sizing
Refer to Figure 16 and Table 1 for vent pipe materials and
sizing. Examples of the vent terminations are shown in
Figures 17 and 18. If the installation requires a vent riser,
suitable drainage must be provided to ensure condensa-
tion does not accumulate. Termination through a roof is
shown Figure 19.
40, 50 and 60-gallon heaters with rated inputs of 50k
Btu/hr or less are supplied with a 2” termination elbow, a
plastic “rodent screen” and a wire mesh "rodent screen"
(see Figure 14).
50 and 75-gallon heaters with rated inputs of 60k Btu/hr
or more are supplied with a 3” termination elbow, a plastic
“rodent screen” and a wire mesh "rodent screen" (see
Figure 15).
with 3 in. venting
with 4 in. venting
VENT LENGTH GREATER THAN
50 EQUIVALENT FT.
(15.2 METRES) USE THIS SCREEN
(FIELD SUPPLIED).
VENT LENGTH GREATER THAN
125 EQUIVALENT FT.
(38.1 METRES) USE THIS SCREEN
(ORDER KIT # 9008310015).
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.
(6.1 METRES) USE THIS SCREEN
(SUPPLIED).
VENT LENGTH GREATER THAN
20 EQUIVALENT FT.
(6.1 METRES) USE THIS SCREEN
(SUPPLIED).
Figure 14
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Rodent Screens
A vent termination 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 Figures
14 & 15). How to determine the “equivalent length” is shown
in Figure 16 and in Table 1. This will allow for easy removal
for inspection and cleaning.
For heaters with rated inputs of 50k Btu/hr or less see
Figure 14.
For heaters with rated inputs of 60k Btu/hr or more see
Figure 15.
with 4 in. venting
VENT LENGTH GREATER THAN
125 EQUIVALENT FT.
(38.1 METRES) USE THIS SCREEN
(FIELD 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.
(6.1 METRES) USE THIS SCREEN
(SUPPLIED).
VENT LENGTH GREATER THAN
20 EQUIVALENT FT.
(6.1 METRES) USE THIS SCREEN
(SUPPLIED).
Figure 15
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