Bradford White 120T400, Руководство по установке и эксплуатации

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Figure 14. Vent Terminal (Low Ground Clearance).
Maximum Vent Length
Table 3. Direct Vent Maximum Vent Length (Combined Maximum Length for Intake and Exhaust)
119 GAL
INPUT
(BTUH)
Max Vent
Length
(feet) 4"
Max Vent
Length (feet)
6”
399,999
120
240
499,999
120
240
Note: The venting distance shown in the chart above is the combined maximum distance for the intake and
exhaust pipe and elbows. The intake and exhaust vent terminals may be in different locations (i.e., different walls
or one wall, one roof) provided the intake equivalent venting distance does not exceed the exhaust by more than
30 feet.
Determining required vent length
1. Determine the total length of straight vent pipe (in feet) required for both the intake and the exhaust.
2. Add 5 feet of venting for every 90° elbow.
3. Add 2 ½ feet of venting for every 45° elbow.
4.
Total vent length cannot exceed “Max Vent Length” in Table 3.
5. Air intake cannot exceed exhaust by more than 30 feet in any venting situation.
Example of Total Power Direct Vent Length for 120T400
A 4” venting system has a total of six 90-degree elbows and a total straight pipe length of 65 feet (includes both intake
and exhaust pipe).
Equivalent vent length for elbows: 6 x 5 feet = 30 feet.
Total equivalent vent distance = 65 feet + 30 feet = 95 feet total equivalent vent length. This is below the
maximum allowed distance of 120 feet for this model using 4” vent.
NOTICE
Do not include the 4” condensate elbow or vent terminals in determining maximum vent length.
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