Carrier 37HS Terminal Selection And Layout, Ð Optimum Outlet Discharge, Ð Location Guidelines

Additional Guidelines for Heating Ð In addition to down- blow slot boot diffusers and Moduline director diffusers, round nozzles spaced along the perimeter wall will also provide satisfactory overhead heating distribution. Some guidance for outlet use are shown in Tables 1 and 2.

Moduline heating and cooling is less ¯exible than sepa- rate duct system heating with Moduline cooling because:

·Moduline heating/cooling is a changeover system requir- ing complete replacement of the cooling duct supply air with heated air, making zone control difficult.

·Moduline location is a compromise between obtaining out- side wall coverage with hot air and good cooling distribution.

Thus, separate duct heating can provide heat for a given exposure without materially affecting the building cooling system. The heating outlets and Moduline terminals can be located in the most efficient air distribution places of the con- ditioned space.

Table 1 Ð Optimum Outlet Discharge

DIFFUSER SLOTS	VELOCITY (Fpm)	TEMPERATURE (F)
Downblow slots	500 to 1250	90 to 115
Round nozzles	900 to 1800	90 to 125
One-way blow slots	600 to 2200	80 to 105
Director Diffusers	800 to 2200	90 to 105

Table 2 Ð Location Guidelines

DIFFUSER STYLE	MINIMUM	MAXIMUM
	DISTANCE (ft)*	DISTANCE (ft)*
Round Nozzles and	1.0	2.0
Downblow Slots
One-Way Blow Slots	0.5	L²
Director Diffusers	2.5	L²

*Feet away from outside wall. ²See Fig. 8.

TERMINAL SELECTION

AND LAYOUT

Introduction Ð Selecting the terminals and making a layout is one of the most important steps in the design pro- cess. This is where you use your knowledge to lay out the job at a low cost and still give your client a satisfactory job.

There are 4 items which must be considered when select- ing an air terminal:

·air volume (Cfm) per terminal Ð a function of 1) the de- sired sound level in the space, and 2) cost

·layout Ð a function of 1) the proper room air motion and

2)physical spacing

·unit combinations and run-out duct

·controller location

De®nitions Ð Following are de®nitions of terms used when discussing the layout of a Moduline system.

Moduline units are arranged as single units or as units in an air series.

SINGLE UNIT Ð A single unit is connected to the supply duct and supplies conditioned air to a space or part of a space. Fig. 9.

AIR SERIES Ð Units in air series are connected unit-to- unit or with interconnecting ductwork and the supply air for all units enters the ®rst unit in the series. Fig. 10.

MASTER UNIT Ð A Moduline unit with controller, alone or in air series, is a master unit. Fig. 11.

SLAVE UNIT Ð A unit in air series, controlled by another unit (master unit) is a slave unit. Fig. 11.

CONTROLS Ð System-powered controls are installed at the jobsite and consist of the components shown below:

Constant Volume Ð Filter and volume controller.

Variable Volume, Diffuser Thermostat Ð Filter, volume con- troller, thermostat with aspirator.

Variable Volume, Wall Thermostat Ð Filter, volume con- troller, wall thermostat.

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