Velocity Shadow Series, Installation And Operating Instructions Manual

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TABLE 7.1: VENT/ AIR INTAKE FITTING EQUIVALENT LENGTH
CPVC/PVC FITTING EQUIVALENT LENGTH (ft)
2” 90 ELBOW (“SANITARY BEND”) 2.6
3” 90 ELBOW (“SANITARY BEND”) 4.0
2” 90 ELBOW (“SHORT BEND” ) 6.0
3” 90 ELBOW (“SHORT BEND”) 10.0
2” 45 ELBOW 1.5
3” 45 ELBOW 2.0
2” COUPLING 0.0
3” COUPLING 0.0
FIGURE 7.2: CPVC AND PVC ELBOWS
4. Minimum Vent and Air Intake Lengths - Observe the minimum vent lengths shown in Tables 7.5, 7.11 and 7.15.
5. Clearances to Combustibles - Maintain the following clearances from the vent system to combustible construction:
• Vent - 1/4” (also observe clearances through both combustible and non-combustible walls - see 9 below)
• Air Intake - 0”
• Concentric Portion of Concentric Terminals - 0”
6. Pitch of Horizontal Vent Piping - Pitch all horizontal CPVC/PVC vent piping 1/4” per foot so that any condensate which
forms in the piping will run towards the boiler.
Les chaudières de catégories I, II et IV doivent présenter des tronçons horizontaux dont la pente montante est d’au moins
5/8 po par pied (52 mm/m) entre la chaudière et l’évent.
7. Supporting Pipe - Vertical and horizontal sections of pipe must be properly supported. Maximum support spacing is 4 feet.
Les instructions d´installation du système d´évacuation doivent préciser que les sections horizontales doivent être
supportées pour prévenir le fléchissement. Les méthodes et les intervalles de support doivent être spécifiés. Les
instructions divent aussi indiquer les renseignements suivants:
• les chaudières de catégories II et IV doivent être installées de façon à empêcher l´accumulation de condensat: et
• si nécessaire, les chaudières de catégories II et IV doivent être pourvues de dispositifs d´évacuation du condensat.
8. Allowing for Thermal Expansion -
• Design the vent system to allow 3/8” of thermal expansion for every 10ft of CPVC/PVC pipe. The boiler will always
act as an anchor to one end of the vent system. If at all possible, select and install hangers and wall thimbles so that
the vent system can expand towards the terminal. When a straight run of pipe exceeds 20ft and must be restrained at
both ends, an offset or expansion loop must be provided ( Figures 7.3a, 7.3b). When a straight horizontal run of pipe
exceeds 20ft and is restrained at one end with an elbow at the other, avoid putting a hanger or guide less than “Y”
inches from the elbow in the adjoining straight section (Figure 7.3c). Thermal expansion fittings are not permitted.