Carrier 37HS Ð Lay Out Terminals, Ð Recommended Maximum Cfm Per Terminal, Ð Terminal Location

As a result, slightly higher maximum cfm per unit is al- lowed as compared to interior zones or the north perimeter, which have relatively constant loads.

The maximum cfm per unit also is affected by the desired sound level in the room and the type of use of the space.

For example, an executive office uses low sound levels but the furnishings generally absorb more sound so the al- lowable cfm/unit is only slightly lower than other types of rooms.

Table 3 Ð Recommended Maximum Cfm

Per Terminal

				MODULINE UNITS
TYPE OF		37HS1		37HS2		37HS4
		East	Interior	East	Interior	East	Interior
SPACE USE
		West		West		West
			and		and		and
		and		and		and
			North		North		North
		South		South		South
General		110	95	220	190	400	350
Office
	With	100	90	200	180	330	300
Private	Carpet
Office	With	90	80	180	160	300	270
	Tile
Executive		85	75	170	150	280	250
Office

Step 2 Ð Lay Out Terminals

LOCATE UNITS IN T-BAR GRID Ð In making a layout, begin with a plan view of the ceiling. Normally, the ceiling grid and the lighting is done ®rst and the diffuser plan must ®t the layout.

The center of the room is the ideal location, but where that space has been reserved for lighting, the Moduline dif- fuser has enough ¯exibility to provide good distribution when not centered in the room.

For a two-way blow diffuser, anywhere from the 1¤4 point to the 1¤4 point (wall to wall) is usually suitable. Outside of the 1¤4 points, a one-way blow diffuser may be needed. Use two-way blow diffuser wherever possible and one-way blow only when really necessary. (See Fig. 14.)

Fig. 14 Ð Diffuser Locations for

Preferred 2-Way or One-Way Blow

Most jobs use a 2- x 4-ft grid T-Bar ceiling with 2- x 4-ft or 2- x 2 ft tiles.

The ®rst consideration in making a layout is to place the terminals as economically as possible in the grid, which means locating the terminals perpendicular to the main tees.

Main tees (the ones with hangers) are 4 ft on center (nor- mally) and the cross tees are spaced 2 ft apart between the mains to make up a 2- x 4-ft T-bar grid. Additional trim tees may be used to divide the ceiling into a 2- x 2-ft grid.

The Moduline units use mounting brackets and hang from (run perpendicular to) the main tees. While the units can be installed anywhere between mains, the most common loca- tion is on the center line of the cross tee (replaces the cross tee). The next most common location is half way between cross tees. See Fig. 15.

While less desirable, the units can be run parallel to the main tees. Unless absolutely necessary the units should not replace the main tee because this means the main tee must be cut. A location halfway between the mains is common and in this case additional hangers are required to the upper plenum of the unit or to the cross tee near the unit.

Special units are available for many other types of ceilings.

Fig. 15 Ð Terminal Location

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