Aprilaire 1700 installation instructions Ventilation / Fan Cycling Settings

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.

FIGURE 12	OPTIONAL		DEHUMIDIFIER
	VENTILATION	24 VAC
	DAMPER			CONTROL
		(10 VA min)
		TRANSFORMER			VENT DEH
				DAMPERS
THERMOSTAT	HVAC EQUIPMENT
R		R			Rf
C		C		HVAC	Cf
G		WIRE NUT			Gs
		G		EQUIP.	Gh W
W		W
Y		Y			Y
				SWITCH	FLOAT
OPTIONAL OUTDOOR				SENSOR	ODT
TEMPERATURE SENSOR
(Model 8052)
					A
				REMOTE	B +
					-
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 13			(shown set
			to 1 hour)
CYCLE PERIOD
	1	ON	30 MIN.
	2		1 HOUR
	3		2 HOUR
	4		3 HOUR

90-783C

FIGURE 14			(shown set to
			30 minutes)
30
0		MIN.	60
	MIN			MIN.
	OFF			TEST

CYCLE TIME

90-783C

FIGURE 15

SYSTEM SETUP

OFF				ON
MODEL 70	1	ON	MODEL 70
HVAC FAN	2		HVAC FAN
WHL HOUSE	3		CONVERTIBLE
VENT-AUTO	4		VENT-TIMED
			90-969

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