Aprilaire 1770A - CENTRAL; ZONED (CONVERTIBLE) INSTALLATION AND OPERATION (CONTINUED)

SINGLE ZONE – DUCTED TO HVAC SYSTEM INSTALLATION (CONTINUED)
•HVACFANON:ActivatingtheHVACfanduringdehumidificationis
recommended because it offers better circulation and balancing of indoor air
conditions. Running the HVAC fan during dehumidification does not affect
moisture removal efficiency. If the switch is put in the HVAC FAN OFF position,
air is pulled through the unit, dehumidified, and circulated solely by the
dehumidifier blower.
•CYCLEPERIOD:Thisdetermineshowfrequentlythedehumidifierwillsample
the air to check the humidity level. Set to 1 hour and adjust as needed.
•ForVentilationswitchsettings,seeVENTILATIONsectionbeginningonpage14.
•ForLocal/Externalswitchsetting,seeMODEL76EXTERNALCONTROLonpage
19 or MODEL 8910 HOME COMFORT CONTROL
™
OR THIRD-PARTY CONTROL
on page 21.
FIGURE 14 – Single Zone – Ducted to HVAC
System, DIP Switch Settings
90-1538
LOCAL
PRIMARY/SECONDARY
EXTERNAL
CYCLE PERIOD
SYSTEM SETUP
1 HOUR
30 MIN.
3 HOUR
2 HOUR
HVAC FAN ON
VENT-TIMED
VENT-AUTO
PRIMARY
HVAC FAN OFF
ON
1234 4321
ON
•SamplingwilloccurattheendofeachCyclePeriod.Attheonsetofsampling,thedehumidifierdamperoutputturnson,thedehumidifier
blower turns on, and the green Status LED flashes.
•Afterthreeminutes,thedewpointoftheincomingairismeasuredandcomparedtothesettingonthecontrolknob.Ifthedewpointofthe
incoming air is above the setting, the compressor turns on and the green Status LED switches to solid illumination. If the dew point is below
the setting, the dehumidifier damper output turns off and the dehumidifier blower turns off along with the green Status LED.
•Thedewpointoftheincomingairiscontinuouslymonitoredduringcompressoroperation.Whenthedewpointoftheincomingairfallsbelow
the setting on the control knob, the dehumidifier damper output turns off and the dehumidifier compressor and blower turn off along with the
green Status LED.
SEQUENCE OF OPERATION (Refer to pages 19-21 for sequence with alternate controls.)
DIP SWITCH CONFIGURATION
SINGLE ZONE – NOT DUCTED TO HVAC SYSTEM INSTALLATION
In this installation the dehumidifier is not ducted to the HVAC system and is used to
dehumidify a specific area. This installation is typically used in basements or crawl
spaces. The dehumidifier can remain non-ducted, however, to achieve specified
performance it is recommended that the dehumidifier be ducted to the area requiring
dehumidification. When ducted, grilles should be installed on the inlet and outlet
to increase the pressure drop across the unit. 10 feet is the recommended distance
between inlet and outlet grilles.
For spaces that can be hard to access, like crawl spaces or basements, the Model
76 Control can be installed as a remote control. See page 20 for the MODEL 76
REMOTE CONTROL application.
Required Components
Duct Work
Grilles with 8” dia. duct collars – 1750A
Grilles with 10” dia. duct collars – 1770A
Optional Components
Condensate Pan & Normally Closed Float Switch
Grilles
Model 76 Control
Model 8910 Home Comfort Control
™
Third-Party Control
9