[4] APACS AIR DISTRIBUTION            

 WHY APACS PROVIDES CLEANER AIR

TRADITIONAL AIR DISTRIBUTION		Fig. 3.1 Conditioned supply air at 45-55°F [7-13°C] at ceiling must be mixed with room air to prevent chill Mixing induces secondary room air flow Suspended particles recirculate throughout space Unhealthy cross contamination
ARGON AIR DISTRIBUTION		Fig. 3.2 Supply air at 65-70°F [18-21°C] from the floor absorbs heat from people and equipment Warmer, lighter air rises carrying contaminants for removal at ceiling level air returns Results in 80% lower particle counts1 creating a greener, healthier environment

¹ Oguro, M., et al., “Evaluation of a Floor-Based Air-Conditioning System Performance in an Office Building,” Pan Pacific Symposium, “Building and Urban Environmental Conditioning in Asia,” Japan, 1995.  

[5] HOW DOES APACS WORK? 

APACS puts moving conditioned air under your control at less than walking speed to produce gentle but effective cooling.  Eight factors affect your personal comfort.  Each of us perceives these eight factors differently.

TEMPERATURE			PHYSIOLOGY
HUMIDITY			CLOTHING
INFRARED ENERGY			AIR QUALITY
PHYSICAL ACTIVITY			AIR MOVEMENT

Presently, of the eight factors affecting comfort, only temperature is controlled by a thermostat, which is somewhere on a wall, not where you are.  The other seven factors are uncontrolled by conventional wall thermostats.  For example, infrared heat from lights, computers and other equipment, and the sun - you feel it, the thermostat does not. 

Personal comfort is achieved when the amount of heat removed from the body is equal to the amount of heat generated and received.  APACS air movement under your control compensates for the seven uncontrolled personal comfort factors, keeping you always comfortable.

Your comfort is directly related to air speed, like the relief felt from a cool breeze on a hot day.  That is exactly what “perceived temperature” means (Fig. 1).  As air speed increases, perceived temperature decreases.  For example, 80°F [27°C] feels like 72°F [22°C] when the air is moving at 1.7 MPH [.76 m/s], or 150 FPM, only about half walking speed.  With ARGON you can adjust the air flow to optimize your comfort over a range of perceived temperature from approximately 65° [18°C] to 80°F [27°C].

Fig. 3.3 [Adapted from ASHRAE Std 55-1992]

DISPLACEMENT VENTILATION

[Click here] to see: "Thermal Displacement Ventilation - The Time is Now!" from e-News by Energy Design Resources.

TECHNICAL SUMMARY

[Click here] to see a Technical Summary of APACS design (PDF file). 

APACS PREVENTS AIR LEAKAGE

Buildings are not airtight.  Existing data show significant levels of air leakage and consequent energy loss in buildings.  These losses are exaggerated with the use of pressurized underfloor air plenums.  APACS prevents underfloor losses by operating the plenum at near atmospheric pressure.

[Click here] to see "Myths About Building Envelopes" for more on air leakage in buildings and its effect on energy consumption.

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