Localized Dehumidifier Operation And Installation - Aprilaire 1700 Safety And Installation Instructions Manual

WHOLE-HOUSE, RETURN TO SUPPLY
This installation (Figure 2) is similar to the "Principle Living Space to Supply" installation, except that the inlet to the
dehumidifier will come from a bypass duct from the HVAC system's return duct rather than the principle living space.
Note: An optional powered damper (6508) is recommended to be installed on the dehumidifier outlet to prevent airflow from
recirculating through the dehumidifier when the HVAC system is on and dehumidifier is off. A wiring connection is
provided. A 24-volt transformer (not provided) is required to power the damper.
A barometric or other backdraft damper should not be used due to the large pressure drop.
FIGURE 2

LOCALIZED DEHUMIDIFIER OPERATION AND INSTALLATION

In this configuration (Figure 3), the dehumidifier will pull air from the principle living space and return it to the same space.
If wired to the HVAC system (necessary for whole house air cycling, see CONTROL AND SETUP section on page 12 for
detailed information), the dehumidifier will still turn on with the first HVAC blower call in each time interval. If no HVAC
blower call occurs during a time interval or the unit is not wired to the HVAC, the dehumidifier will activate its own internal
blower and take an air sample. If the incoming air is above the set point, the dehumidifier (compressor) will turn on and run
until the set point is satisfied. We recommend air cycling be enabled to move this drier air throughout the house.
FIGURE 3 – LOCALIZED DEHUMIDIFIER CONFIGURATION
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