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the power light is off, return the P2621-NO2/VC to your supplier or CONSPEC factory
for repair or rep1acement.
2. The Fan Does Not Operate When Fan Light (yellow light) is ON or
The Fan Does Not Turn OFF When The Fan Light (yellow light) is OFF
Turn OFF the power to the P2621 and to the fan Control system. Check that the field
installed relay in the fan motor circuit is a (NC~ Normally Closed type.) Open the
enclosure and check that the ventilation fan wiring is securely attached to the terminals
K1 and K2, and that the wiring from the Connector terminals to the circuit board is
securely attached. Disconnect the ventilation fan wiring from terminals K1 and K2. Using
an ohmmeter, measure the resistance between terminals K1 and K2. The circuit should be
open (high resistance). If the circuit is not open, return the P2621 to your supplier or
CONSPEC for repair or replacement. Turn on the 24 VAC power to the P2621-NO2/VC
and wait for -FAN- to appear in the display using an ohmmeter, measure the resistance
between terminals K1 and K2. The circuit should be open (high resistance). If the circuit
is not open, return the P2621 to your supplier or to CONSPEC for repair or replacement.
With the 24VAC power to the P2621-NO2/VC turned OFF, wait for - FAN- to disappear
from the display. Using an ohmmeter, measure the resistance between terminals K1 and
K2. The circuit should be closed (low or zero resistance). If the circuit is not closed,
return the P2621-NO2/VC to your supplier or CONSPEC for repair or replacement. If the
above resistance checks between terminals K1 and K2 are fine, turn OFF the 24 VAC
power to the P2621-NO2/VC and reconnect the fan Control wiring. Turn ON the 24 VAC
power to the unit and fan Control system. Check the fan operation. If the fan does not
operate properly the problem is in the ventilation fan Control system or the Connecting
wiring.
3. Fault Light Is ON
Turn OFF the 24 VAC power to the P2621-NO2/VC then turn it ON. If power cycling
does not remove the fault condition turn OFF the 24 VAC power and power to the
ventilation fan Control system. Open the enclosure and check that the connector from the
sensor is attached to the main board. Turn ON the 24 VAC power to the P2621-NO2/VC.
If the above steps do not remove the fault condition, turn OFF the 24 VAC power to the
P2621-NO2/VC and return the unit to your supplier or Conspec for repair or replacement.
The sensor is factory calibrated and the P2621-NO2/VC is ready to install and use. An
optional field calibration kit is available when local regulations require periodic
calibration checks of the sensor. When the sensor is about to fail, the red fail LED will
light intermittently and will light steadily when the sensor fails. If the sensor is not
replaced the P2621 will turn on the fans and go into the fail mode. The plug-in sensor
module must be replaced before the unit can be reset.
Conspec Technical Services: 724-489-8450
