Aprilaire 8120 Installation Instructions

STEP 9: SET THE SAmPLING TImE INTERVAL
A. The Cycle Time Interval is the time period over which ventilation
will occur. This is variable from 1 to 4 hours depending on FIGURE 7 – Cycle Time
customer preference. Keep in mind, once the Ventilation
requirement is met the Vent Control won't run again until the
start of the next cycle. The Cycle Time is the length of the
CYCLE TIME
1 HR 3 HR
sampling period, while the Ventilation time as set is the actual
operating time.
B. The device is factory set to a 1 hour sample time. This is 2 HR 4 HR
recommended for a quicker reaction to conditions. Also the
longer Cycle Intervals are more likely to require more than the
60 minutes available on the dial.
C. Remove knob by carefully pulling it out from the case. Snap the
cover off and refer to Figure 7 to locate the cycle time setting
tab and pins.
D. The jumper tab on the 5 pin array determines the sampling time
interval. Per diagram this can be 1,2,3 or 4 hours. The jumper
tab is removed by pulling it straight out from the pins. Take care
in replacing, do not bend.
STEP 10: DETERmINE THE VENT CONTROL KNOb SETTING
A. The run time in minutes is set with the knob. The Time 0 setting keeps the circuit live but the
vent won't operate. OFF deactivates it completely. Any setting made is the total running
time per 1, 2, 3 or 4 hour cycle.
B. Record your entries from Steps 7C and 8C in the Table on page 6. From this you can determine
the correct knob setting. For example, if 80 CFM is required but the Vent delivers 120 CFM set
the knob to 40 minutes. The knob settings as listed are for a 1 hour cycle time.
C. All values can be set except those in the black area. If the Vent Control is clocked out (black
area) and if the cycle is set to 2, 3 or 4 hours, reset the pin jumper to get a settable time. For
example, if 80 minutes is required at 2 hours, at 1 hour this would be a settable 40 minutes. If
you're still clocked out or are already set to a 1 hour cycle consult with the homeowner about
installing a second device.
5
Step 7C
20
CFm Required >>
Step 8C
KNOb SETTINGS (in minutes) FOR AIRFLOW DELIVERED vs AIRFLOW REQUIRED (1 HR CYCLE)
CFm Delivered
60
20
80
15
WIRING AND
CYCLE TIME
JUMPER
1 HR 3 HR
CONFIGURATION 100
15
2 HR 4 HR
G
S TO STAT C R D D T T
G H TO HVAC 120 10
W TO HVAC
10005991
140
10
160
10
OUTDOOR
TEMPERATURE
SENSOR
STEP 11: SYSTEm CHECK OUT
90-698
A. For system test be sure that 24 VAC is applied in series with the 6506 damper (normally closed) and the A/A terminals on the Vent Control.
Check the wiring as described in Step 6.
B. Turn knob on Control dial to TEST position. If the installation is correct the blower will turn on (independent of heat or cooling operation)
and the damper will open. The vent system will operate for 1 minute unless the knob is turned off of TEST. If system does not operate in the
TEST Mode check the Troubleshooting Guide.
C. Return knob to the calculated setting. Do not leave in TEST, the Vent Control won't operate normally.
FIGURE 8 – Set Vent Time TROUbLESHOOTING
PRObLEm
HVAC blower doesn't turn on
in Test mode.
90-702
Damper does not open
in Test.
The Vent Control doesn't
turn off after the knob is
turned off Test.
The damper does not open
with the blower operating.
INSTALLATION TEmPLATE
4-11/16" x 2-15/16" cutout
blower turns on unexpectedly.
P.O. BOX 1467 • Madison, WI 53701-1467 • Phone: 800/334-6011 • Fax: 608/257-4357 • www.aprilairecontractor.com
30 40 50 60 70 80 90
30 40 50 60 70 80 90
25 30 40 45 55 60 70
20 25 30 35 40 50 55
15 20 25 30 35 40 45
15 15 20 25 30 35 40
10 15 20 25 25 30 35
TROUbLESHOOTING PROCEDURE
1. Make sure you turned the power back on to the HVAC equipment.
2. Check the wiring diagram for the R, C, W and GSTAT and GHVAC at both the HVAC equipment and the Vent Control.
3. Make sure the Outdoor Sensor Terminals on the Control are connected with either the Temperature Sensor, the Time
Only Insert or a jumper wire. If nothing is connected here the Control will not function.
4. Check voltage across the Vent Control R&C terminals. Voltage should be in the 22 VAC to 30 VAC range.
5. Remember, once the Test minute is up the system won't operate.
1. Follow above procedure.
2. Check wiring diagram to make sure the damper is wired in series with the circuit board and transformer.
1. This might be okay, the thermostat might have activated. Also the blower might be set up for continuous operation.
The Vent Control should deactivate once the time setting is reached.
2. If the pins are set to 1 hour and the knob is turned to 60 minutes the Vent Control will not turn off. But for a 2 hour
pin setting, if the knob is at 60 minutes, at the end of that 60 minutes the Vent will turn off.
1. The damper will not operate once the time interval has been met. If the knob is turned to 5 minutes and 5 minutes
has elapsed, the damper will close and it will stay closed until the pin setting interval is met.
2. If the Indoor RH is above 55% and the outdoor temperature is above 50° the damper will not open because of the
potential for excess humidity.
3. If the outdoor temperature is below 0° or above 100° the vent stays off.
4. Verify that the outdoor temperature sensor is located within 3 feet of the vent inlet, or if located outside that it's not
in direct sunlight at any time.
5. Turbulence in the return duct, plenum or mixing box can give false readings. Make sure the Vent Control is at least
6 inches upstream of the fresh air intake port in the return to minimize this effect.
1. The Vent Control will activate the blower whether or not heat or A/C is on call. This ensures ventilation even if the
thermostat is lowered.
2. To verify proper operation see if the blower turns off by turning down the knob. Return to its original setting.
RESEARCH PRODUCTS CORPORATION
6
100
100
75
60
50
45
40
Model 8120 and 8126
Safety & Installation Instructions
FAMILIARIZE YOURSELF WITH THE INSTALLATION INSTRUCTIONS BEFORE STARTING
To prevent serious injury from electrical shock this product must be installed by a qualified HVAC contractor.
DANGER
120 volts can cause serious injury from
electric shock. Disconnect electrical power
to the HVAC system before proceeding.
WARNING
Sharp metal edges can cause serious injury
from cuts. Use gloves when cutting plenum
openings and handling ductwork.
10007162 2.09
B2204388B
Ventilation Controller
DANGER
ATTENTION INSTALLER:
CAUTION
Do not mount the Vent Control on the supply plenum or duct. The unit
will malfunction at heated temperatures and lose its calibration.
When installing the Vent Control on downflow furnaces, ensure that
the blower continues to run after the heat call is satisfied to prevent
high temperatures from damaging the Control circuit board.
Do not mount the Vent downstream from any fresh air intake port,
humidifier or bypass outlet. False humidity conditions will cause the
Vent Control to operate incorrectly.