17
to 50mm) of clearance is suggested.
For the best air distribution, the unit should be centered against the longest wall, distributing the
cold air as close to heat load as possible, unless the unit is ducted. The unit should not be placed
near any corner of the room or at the end of a long, narrow room. Install the units as close as
possible to the largest heat load. Multiple units should be evenly spaced, as far apart as possible.
It is recommended to install an under-floor water detection system.
NOTE:
Condensation formation and frequent humidifier flushing are
normal functions of this equipment. Proper drain connections must be
made to ensure proper removal. Unit will require water connections for
condensate removal and possibly for humidifier makeup water, chilled
water and/or hot water. Installation of units above equipment that could
sustain water damage should be avoided
2.8.
Downflow Units
Downflow units will typically sit on an elevated flooring system known as a raised floor. The unit
dis- charges air downward which pressurizes the raised floor and channels upward through
perforated floor tiles. Location and quantity of perforated tiles will dictate proper air distribution.
If the raised floor is strong enough to support the unit and local codes permit, the unit can be
placed directly on top with cutouts made for the discharge openings.
Verify that the raised floor has been properly sized for the u
nit’s airflow and the room is free of
airflow restrictions. Perforated floor tiles in the raised floor should ensure minimal pressure loss.
The raised floor must
provide a minimum of 12” (305 mm) clearance. Ensure that there is
adequate clearance above the unit for service, such as replacing filters. Optional plenums are
available for downflow unit ducting.
Figure 5 Typical Return & Discharge Air Distribution