Aprilaire 1700 - Manual (Page 10)

10
VENTILATION / FAN CYCLING SETTINGS
The Aprilaire Dehumidifier has the option
to monitor HVAC heating, cooling and fan
calls to assure the HVAC fan has
operated a predetermined amount of
time each 1/2, 1, 2 or 3 hours. The
dehumidifier can also open a normally
closed damper in an outdoor air intake to
ventilate during this predetermined
amount of time. This feature will
function even if the dehumidifier is
turned off at the dehumidifier or Model
70 Living Space Control. The only way to
disable this feature is by turning the
Cycle Time setting to OFF or turning
power off at the On/Off switch.
HVAC EQUIPMENT THERMOSTAT
WIRE NUT
DEHUMIDIFIER
CONTROL
24 VAC
(10 VA min)
TRANSFORMER
DAMPER
VENTILATION
OPTIONAL
G
R
C
G
W
Y Y
W
C
R
A+
B
DEH
REMOTE
HV
AC EQUIP
.
VENT
Cf
Gs
Gh
W
-
Y
Rf
DAMPERS
OPTIONAL OUTDOOR
TEMPERATURE SENSOR
(Model 8052)
SENSOR
ODT
SWITCH
FLOA
T
FIGURE 12
90-968
First, set the 1/2, 1, 2 or 3 hour period by setting the CYCLE PERIOD dip switches to determine
how often the dehumidifier should look to ventilate or cycle the HVAC fan.
Next, use the CYCLE TIME dial to determine how long during every cycle period the HVAC fan
should operate. Adjust the dial from OFF to between 1 to 60 minutes. This will give you HVAC fan
operation from 1 to 60 minutes every 1/2, 1, 2 or 3 hours. A call for heat, cooling or fan from the
HVAC equipment will often satisfy the run time requirement. If not, the dehumidifier will turn on
the HVAC fan to assure that the cycle time is met. For example: If the home requires
ventilation of 20 minutes every two hours set the CYCLE PERIOD Dip Switch for 2 hours
to ON and rotate the CYCLE TIME to 20 minutes. If the HVAC equipment only has to run
for 10 minutes, the dehumidifier will turn on the HVAC fan for 10 minutes at the end of
the 2 hours to assure the ventilation / fan cycling time.
Finally, if using the Ventilation Damper, determine if the ventilation should be restricted based
on outdoor temperature. Set the VENT-AUTO / VENT-TIMED dip switch to VENT-AUTO
(see Figure 15) to prevent opening the ventilation damper if the outdoor air is above 100°F,
below 0°F or except with a heat call between 20°F and 0°F. In the VENT-TIMED setting the
ventilation damper is activated regardless of outdoor conditions. Note: The Outdoor
Temperature Sensor (Model 8052) must be installed for this to work.
You can also check the wiring of the dehumidifier to the HVAC equipment. If you rotate the
CYCLE TIME dial to TEST, the HVAC fan should come on and the Ventilation Damper
(if equipped) should open. DO NOT leave the CYCLE TIME in TEST.
FIGURE 14
90-783C
FIGURE 13
ON 1234
2 HOUR
3 HOUR
30 MIN.
1 HOUR
CYCLE PERIOD
90-783C
CYCLE TIME
TEST
60
MIN.
OFF
0
MIN
MIN.
30
MIN.
(shown set
to 1 hour)
FIGURE 15
4
3
2
1
ON
VENT-TIMED
HVAC FAN
SYSTEM SETUP
ON
MODEL 70
CONVERTIBLE
HVAC FAN
WHL HOUSE
VENT-AUTO
MODEL 70
OFF
90-969
(shown set to
30 minutes)