User Guide

Troubleshooting
Refer to the Operation section for proper operation.
Table 2: Troubleshooting Chart
Problem Possible Cause Possible Solution
Input pressure is below operating
range.
No problem, normal operation.
No 24 volt control voltage Check for 24 VAC at control.
No input pressure to control Alignment. Schrader valve depressor
must depress Schrader valve enough to
allow pressure into capillary.
Bad fan motor Disconnect power. Place a jumper from L
1
to M
1
and connect power. If fan does not
start, motor is bad and should be
replaced.
No Fan Operation
Pressure transducer problem See Pressure Transducer
Troubleshooting section.
Fan stops when pressure reaches
the high end of the operating range.
Control is not wired correctly. See wiring diagrams. Ensure that the
24 VAC power supply is connected
in-phase with the motor power supply.
Control is not wired correctly. See wiring diagrams. Ensure that the
24 VAC power supply is connected
in-phase with the motor power supply.
No Fan Modulation (On-Off
Operation)
Pressure transducer problem See Pressure Transducer
Troubleshooting.
Control is not wired correctly. See wiring diagrams. Ensure that the
24 VAC power supply is connected
in-phase with the motor power supply.
Fan Starts at Full Speed.
Pressure transducer problem See Pressure Transducer
Troubleshooting.
Control is not wired correctly. Check to see if control voltage (24 VAC) is
on same phase as motor.
Dirty or blocked condenser coil Clean condenser coil.
Erratic Fan Operation
Pressure transducer problem See Pressure Transducer
Troubleshooting.
Dirty or blocked condenser coil Clean condenser coil.
Fan motor is cycling thermal
overload.
Wrong motor for fan speed control
application
Replace with motor approved for fan
speed control application.
Pressure Transducer Troubleshooting
1. Disconnect 6-pin connector from right side of
control.
2. Place a jumper wire between third pin from the
top and the bottom pin on the control, not the
cable.
a. If fan goes to full speed, check for input
pressure.
b. If there is adequate pressure, the transducer
is bad and the control must be replaced.
Repairs and Replacement
Field repairs must not be made. For a replacement
control, contact the Original Equipment Manufacturer
or your local Johnson Controls/PENN distributor.
6 P66 Series Electronic Fan Speed Controls Installation Instructions