Crown Boiler BWF061 - Manual (Page 16)

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4) Maximum Vent Pipe Length:
• BWF061 to BWF162 – 39.5 ft + (2) 90 degree elbows + cap
• BWF195, BWF229 (using 4” vent pipe): 37 ft + (2) 90 degree elbows + cap
• BWF195, BWF229 (using 3” vent pipe): 24.5 ft + (2) 90 degree elbows + cap
• Reduce the above maximum straight pipe runs by the equivalent length from Table 4 for each additional elbow
beyond the first two.
Example:
A vertical vent system is planned for a BWF162 that has the following components:
2 ft vertical pipe
1 90 Elbow
1 condensate trap which has an is 18 inch long run
1 90 Elbow
1 ft vertical pipe
1 45 elbow
2 ft sloped pipe
1 45 elbow
7 ft vertical pipe
1 Cap
Since the boiler is a BWF162, all piping must be done in 3” pipe. The first two 90 elbows and the termination cap are
not considered. The condensate trap is treated as a straight length of pipe 1.5 feet in length. The result is 13.5 ft of
straight pipe and two 45 elbows. From Table 4, the equivalent length of the 45 elbow is 4.5ft. The maximum
allowable run of straight pipe on this system is therefore:
37.5 ft – 4.5 ft – 4.5 ft = 28.5ft
Since the planned installation has 13.5 ft of straight pipe, the planned vent length is within the maximum limit.
5) Minimum Vent Pipe Length - 6 ft + (2) 90 degree elbows + cap
6) Permitted Terminals – A cap must be used which is compatible with the rest of the vent system. See Table 6 for the
appropriate cap.
7) Condensate traps – A condensate trap is required on all vertical-venting systems. Install this trap as shown in Figure 13. If
there are additional sections of horizontal piping in the vent system, they must either be equipped with their own
condensate Tees or pitched so that condensate will run into the one required trap.
8) Use only a “horizontal” type condensate Tee (Fig. 9).
9) Pitch of horizontal piping – Pitch the lowest horizontal section of piping ¼” per foot towards the boiler. Other horizontal
sections (if any) must be pitched so that condensate will run towards a condensate Tee.
10) Fire-stops and wall thimbles – A wall thimble is required where the exhaust pipe passes through combustible walls with
less than a 5” clearance. Firestops are required where the vent passes through ceilings. These components must be
compatible with the rest of the exhaust system. Table 5 shows wall thimble model numbers for the approved vent systems.
Table 7 shows firestop model numbers for the approved vent systems.