Roberts Gorden CRV-B-4, CRV-B-8, CRV-B-6 Pipe sizing, Duct Design Rules, Outside Air Blower

SECTION 9: AIR SUPPLY SYSTEM

9.3.3 Pipe sizing

To size each section of pipe proceed as follows:

•Calculate the required flow units at each outlet of the supply system.

•Measure the longest run of pipe from the blower to the most remote outlet. Use only this distance in Figure 27 (or the next longer distance if the exact distance is not shown). This is to provide assurance that the pressure drop to the most remote outlet will not exceed 0.25" w.c. when all outlets are supplied.

•See Figure 27, find the intersection point on the graph for the appropriate duct length and number of flow units. The duct size above this intersection point indicates what size duct work should be used. Proceed in a similar manner for each outlet and each section of duct. For each section of duct, determine the total flow unit capacity sup- plied by that section.

Duct Design Rules

•System should be designed so that the blower is positioned closest to the highest flow require- ments (end vents).

•When a duct is carrying more than 40 flow units, it must be at least 6" diameter.

Blower (P/N 90707501) Performance 112 Flow

Units:

One outside air blower is required per each EP-100 or EP-200 series pump and two outside air blowers may be required for each EP-300 series pump. Outside air blowers cannot be shared between two separate CRV-Series systems.

FIGURE 28: Outside Air Blower

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