Desert Aire Aura QS, Installation And Operation Manual

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2.2 Duct Installation
Duct design and installation should conform to the latest ASHRAE and SMACNA low velocity
duct standards. See section 5.2 for details. Undersized, restrictive ductwork with abrupt turns
or transitions, can decrease the efficiency and the moisture removal capacity of your
dehumidifier. Size the ductwork for an acceptable air pressure drop at the airflow volume of
your dehumidifier. Use neoprene flex connectors when you attach ductwork to the dehumidifier
to prevent transmission of excess vibration and noise.
Select the grilles, registers and diffusers for low static pressure loss, required throw distance,
and the specified CFM rating. You can find this information in most grille manufacturer’s
catalogs. If you are installing the grilles in a corrosive environment, choose components made
from anodized aluminum.
If you must install ductwork in an unconditioned area, use fiberglass duct wrap with vapor
barrier facing. You must install the outdoor air intake away from all sources of airborne
contamination such as exhaust fans or plumbing vents. You can use galvanized sheet metal
ducts for most applications. However, you should use aluminum or stainless steel ducts for
extreme applications such as chemical-laden environments.
2.3 Condensate Drain Piping
Condensate drain lines installed in an unconditioned space must be heat taped to
prevent freezing. Check the heat tape yearly before winter operation.
The condensate drain connection may be on the side or the bottom of the dehumidifier,
depending on the size and style of the cabinet used. Use concrete blocks or steel dunnage to
raise the dehumidifier high enough above the floor to provide clearance for the field-supplied
condensate drain trap.
Note: Dehumidifiers with gas heating option may have condensate form inside the furnace heat
exchanger since it is located downstream from the cooling coil. On indoor units, you must also
connect the heater’s drain line (if present) to your field-installed condensate drainage plumbing.
Note: While the supply blower runs, the drain pan area inside the dehumidifier operates at a
negative pressure. Your unit requires a p-trap in the condensate drain pipe to prevent
condensate from being drawn into the cabinet of the dehumidifier.
Desert Aire - QS/QV Manual