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DUCT WORK:
The duct work requirements for these systems are much more critical than conventional air conditioning
systems.
ALL SUPPLY AND RETURN AIR DUCTWORK FOR THE DEHUMIDIFIER MUST
BE AIR AND VAPOR TIGHT
. This is extremely important for proper dehumidifier performance. Even
though the dehumidifier is removing moisture, it may not perform properly if moisture enters the dry air
stream through leaks in the ductwork. The air ducts must be properly sized to keep pressure losses at a
minimum, and prevent this loss from exceeding the designed fan static capability. It is important to insure that
the reactivation discharge air does not enter the process or reactivation inlets. If the unit is installed indoors,
the reactivation outlet can be connected by duct to the outside of the building. See Unit Outline drawing for
fan external static pressure.
CONDENSATE TRAPS: (Cooling Option)
A pipe nipple is installed on the drain pans of cooling coils for field installation of condensate traps.
All outside air coils and any others operating "wet" must be properly trapped for satisfactory
operation. Under some circumstances, an after cooling coil may require trapping. In these cases, a trap
with a swing type check valve should be installed to prevent air from being drawn into the dry air stream
when the trap is dry.
When a trap is not required for after-cooling coils, the sealed pipe cap must be left in place to
prevent moisture from entering the dry air stream.
To calculate the proper trap depth, the maximum negative static pressure at the drainpipe must be
measured or estimated. This value with a 1.25 factor applied will provide for the minimum column of
water required for the trap.
If there are any questions, consult Bry-Air for assistance and recommendations.
