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Desert Aire - LC/LV Manual
The CM3530 microprocessor controller can be programmed to set occupied and
unoccupied operation times on LC and LV Series dehumidifiers. LC and LV units
ordered with the outdoor air intake option are provided with an automatically controlled
outdoor air intake damper.
When ordered with an outdoor air intake option, refer to the Desert Aire LC/LV control
schematic. NOTE: You must provide a transformer or a power source for the
relay R2 and the outdoor air damper and the exhaust blower contactor. An outdoor air
intake damper can be factory installed and powered by the unit as well.
You must install an exhaust blower whenever you bring outdoor air into a
dehumidified room. Without the exhaust fan, the room would be at a positive pressure.
This increased room pressure can drive moisture and chlorine odors into insulation,
building materials, and adjacent rooms. Size the exhaust blower to maintain the
dehumidified room at a neutral or slightly negative pressure.
You must install the outdoor air intake away from any sources of airborne
contamination such as exhaust fans or plumbing vents. You must also filter the
outdoor air before it comes in contact with any coils. Insects and debris in the
unfiltered air will rapidly clog the dehumidifier’s reheat condenser coil, which will lead
to repeated service calls and eventually equipment damage.
If mixed air temperatures in the system’s blower compartment falls below 45°F an
internal safety thermostat will de-energize and override a call for outdoor air. This
safety mode will remain active until mixed air temperatures in the blower compartment
rise above 55°F.
IF OUTDOOR TEMPERATURES IN CONJUNCTION WITH YOUR
OUTDOOR AIRFLOW RATE ARE CAPABLE OF TRIPPING THE SAFETY
THERMOSTAT, YOU MUST INSTALL AN OUTDOOR AIR PRE-HEATING COIL.
Refer to section 3.2.4 to determine if the pre-heating of outdoor air is required for your
application. An example of proper outdoor air installation is shown in Figure 19.