Aprilaire 1750A Dehumidifier User Manual


 
VENTILATION OR AIR CYCLING (CONTINUED)
SEQUENCE OF OPERATION
VENT-TIMED, HVAC INITIATES VENTILATION
•VentilationwilloccurwheneverthereisanHVACfan(Gs)orheat(W)callandwillcontinueuntiltheventilationtimehasmetthesetCycle
Time during the set Cycle Period. During ventilation the dehumidifier damper output turns on, the ventilation damper opens, the dehumidifier
blower turns on, and the Status LED flashes.
•WhentheHVACheatorfancallhasendedorwhentheventilationtimerequirementhasbeenmet,thedehumidifierdamperoutputturnsoff,
the ventilation damper closes, and the dehumidifier blower turns off along with the green Status LED.
•TwominutesmustelapsefollowingtheendofaHVACfanorheatcallbeforethedehumidifiercaninitiateaventilationcycle.
VENT-TIMED, DEHUMIDIFIER INITIATES VENTILATION
•WhentheamountoftimeremainingintheCyclePeriodisequaltotheamountofCycleTimerequired,theHVACfanturnson,the
dehumidifier damper output turns on, the ventilation damper opens, the dehumidifier blower turns on, and the Status LED flashes.
•Whentheventilationtimerequirementhasbeenmet,theHVACfanturnsoff,thedehumidifierdamperoutputturnsoff,theventilationdamper
closes, and the dehumidifier blower turns off along with the green Status LED.
•Topreventshortcyclingthefan,aventilationcyclewillnotstartunlessthereareatleast2minutesremainingintheCyclePeriod.
DEHUMIDIFICATION DURING VENTILATION
When not controlled by the Model 70 Living Space Control or third-party control, the dehumidifier will continually measure the
conditions of the incoming air during ventilation.
•Thedewpointoftheairismeasured3minutesafterthedehumidifierbloweristurnedonandevery15secondswhiletheblowerisrunning.
•Ifthedewpointoftheairisabovethesettingonthecontrolknob,thecompressorturnsonandthegreenStatusLEDswitchestosolid
illumination.
•Whenthedewpointoftheairfallsbelowthecontrolknobsetpoint,thecompressorturnsoffandtheStatusLEDflashes.
VENT-AUTO
Ventilation in the Vent-Auto configuration is functionally the same as Vent-Timed operation, with the exception of the temperature limits applied
to the incoming air.
•Iftheincomingairtemperatureisgreaterthanorequalto100°F,theventilationdampercloses.Ifthetemperaturedropsto95°Forlower
during the same ventilation cycle, the ventilation damper will open.
•Iftheincomingairtemperatureislessthanorequalto0°F,theventilationdampercloses.Ifthetemperatureincreasesto5°Forhigherduring
the same ventilation cycle and the ventilation cycle was initiated by a HVAC heat (W) call, the ventilation damper will open.
•Iftheairtemperatureislessthanorequalto20°Fandabove0°F,theventilationdamperwillcloseunlessaHVACheat(W)callisinitiated
during the ventilation cycle. If the air temperature drops to 0°F or below during the same ventilation cycle, the ventilation damper closes. If
the temperature rises to 25°F or higher during the same ventilation cycle, the ventilation damper will open.
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