Spot Installation - Aprilaire 1750A Installation Instructions Manual

WHOlE-HOME INSTAllATION
DIP SWITCH CONfIGURATION
• H VAC 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 .
• C YCLE PERIOD: This determines how frequently the dehumidifier will sample
the air to check the humidity level . Set to 1 hour and adjust as needed .
• F or Ventilation switch settings, see VENTILATION section beginning on page 12.
• F or Local/External switch setting, see THIRD-PARTY CONTROL on page 17.
SEQUENCE Of OPERATION
• S ampling will occur once within the Cycle Period. Sampling is initiated with the first HVAC fan (Gs) call or at the end of the Cycle Period if
a HVAC fan call is not received within the Cycle Period . At the onset of sampling, the dehumidifier damper output turns on, the dehumidifier
blower turns on, and the green Status LED flashes .
• A fter three minutes, the dew point of the incoming air is measured and compared to the set point on the control knob. If the dew point of the
incoming air is above the set point, the compressor turns on and the green Status LED switches to solid illumination . If the dew point is below
the set point, the dehumidifier damper output turns off and the dehumidifier blower turns off along with the green Status LED .
• T he dew point of the incoming air is continuously monitored during compressor operation. When the dew point of the incoming air falls below
the set point on the control knob, the dehumidifier damper output turns off and the dehumidifier compressor and blower turn off along with
the green Status LED .

SPOT 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 .
8
(CONTINUED)
fIGURE 13 – Whole-Home DIP Switch Settings
SYSTEM SETUP
LOCAL
HVAC FAN OFF
WHL HOUSE
VENT-AUTO
CYCLE PERIOD
90-1538
Required Components
Duct Work
Grilles with 8" duct collars
Optional Components
Condensate Pan & Normally Closed Float Switch
Model 70 Living Space Control
Third-Party Control
EXTERNAL
HVAC FAN ON
CONVERTIBLE
VENT-TIMED
30 MIN.
1 HOUR
2 HOUR
3 HOUR