FIGURE 6.
DIRECT VENTING - FOR BTPV MODELS
All exhaust vent terminal, flue reducer, and intake vent terminal are supplied with any unit intended for direct venting. These parts must be installed without alteration.
This heater is category III appliance when used in a direct vent application. All national and local codes pertaining to the installation of such an appliance must be followed.
Horizontal portions of the exhaust vent system must be installed with a minimum upward slope of 1/4” (6.35 mm) per foot of length.
Selkirk metalbestos model PS or G vent is approved for use as exhaust venting on these models. Model PS is a
TABLE 4.
Selkirk Metalbestos Model PS
Clearance to Combustibles
Interior | 6” (152.4 mm) |
Exterior | 6” (152.4 mm) |
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TABLE 5.
Dimension in |
| BTPV | ||
Inches (mm) |
| 540A | ||
Flue Outlet Dia. |
| 9 | (229) | |
Flue Reducer Dimension |
| 9 x 8 | ||
(Supplied) |
| (229 x 203) | ||
Min. Exhaust Vent Dia. Inch (mm) |
| 8 | (203) | |
Min. Intake Vent Dia. Inch (mm) |
| 8 | (203) | |
Maximum Number Of |
| 90° |
| 4 |
Elbows, Intake |
| 45° |
| 8 |
Maximum Number Of |
| 90° |
| 4 |
Elbows, Exhaust |
| 45° |
| 8 |
Total Intake Vent |
| Max. | 75 | (23 m) |
Length, Equiv. Ft. |
| Min. | 3 | (1 m) |
Total Exhaust Vent |
| Max. | 75 | (23 m) |
Length, Equiv. Ft. |
| Min. | 6 (1.8) | |
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Note: Barometric draft control is not used in direct vent installations as the venting system must be sealed.
When calculating the equivalent length of a venting system each 90 elbow is equivalent to 10 feet of straight pipe. Each 45 elbow is equivalent to 5 feet (1.5 m) of straight pipe. Do not exceed the maximum number of elbows as shown in Table 5. In no case may the sum of the straight pipe lengths and the equivalent lengths of the elbows exceed the valves in Table 5.
8” diameter PVC or galvanized pipe is approved for use as intake venting on these models. Class 63, 100, 125, 200, and schedule 40 pipe may be used for PVC pipe. Intake venting must be adequately supported to avoid unnecessary stress on vent hood, venting, or burner.
See Table 5 limitations on venting system design for direct vent installations.
VENT TERMINAL LOCATIONS-EXHAUST
See “Horizontal Venting” in this manual for acceptable locations for exhaust hoods.
VENT TERMINAL LOCATIONS-INTAKE
When considering locations for the intake terminal, bear in mind that the terminal:
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