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8. MAINTENANCE AND TROUBLESHOOTING
Follow individual exhaust fan device manufacturer’s troubleshooting and maintenance information.
There is no routine maintenance required for the FAVC (controller) other than making sure the wires
connected to the FAVC terminals are secure and the screws holding the unit to ductwork is tight.
Field Controls Technical Support is available Monday-Friday from 8:00 am to 5:00 pm (EST) at
800.742.8368 or by email at fi eldtec@fi eldcontrols.com for further assistance. To reprint a copy of
the latest revision of this manual, visit www.fi eldcontrols.com to download.
SYMPTOM
TROUBLESHOOTING PROCEDURE
Central fan turns on unexpectedly
If ventilation requirement has not been met, the FAVC will
activate the central fan. This is normal operation.
The fresh air damper does not open
during call for ventilation.
• Damper is not plugged in or properly wired. Check
connector and wiring connections.
• Outdoor temperature is outside the operating limit
temperatures for fresh air ventilation
• Indoor RH is above humidity limits for fresh air
ventilation
FAVC controller LED is:
Green
Blue
Red
No Color
Green LED indicates outside air meets ventilation
requirements without restrictions. This is normal, system
will function normally.
Blue LED indicates the outside air temperature or return air
plenum air temperature is less than 40°F. In this condition,
fresh air ventilation is prohibited.
Red LED indicates the outdoor air temperature is greater
or equal to 90°F and may restrict ventilation to 25%. If
temperature rises to 100°F, fresh air ventilation is
prohibited.
No color LED indicates no power 24VAC power or
common from HVAC system or faulty ODT sensor:
1. Check 24VAC power from HVAC/thermostat.
2. Check wire connections to/from HVAC/Thermostat to
FAVC at terminals.
3. ODT Sensor - Check wire terminal connections. Check
wire nut connections. Disconnect ODT wires from S
terminals and perform ohmmeter check on based on
temperature vs ohm readings. (Chart to left) If ohm
readings do not match temperature scale, replace ODT1
sensor.
ODT Sensor
100°F
80°F
60°F
40°F
20°F
OHM Measurement
5861
9116
13926
26207
46673
Central fan does not turn on during
fresh air damper ventilation and appli-
ance operation
The FAVC DIP Switch 4 is set to ON (Energy Saving Mode).
The controller will turn on/off appliances and fresh air
damper to meet ventilation requirements. This is normal.
P/N 780100700 07/18 Rev F
