Johnson Controls TEC3310 Installation Instructions Manual page 45

Table 12: Troubleshooting Details
Symptom
The controller displays Idle with a
Unit Status of Cooling
Unavailable due to Changeover
despite being above cooling
setpoint, or with a status of
Heating Unavailable due to
Changeover despite being below
the setpoint.
The controller displays Idle with a
Unit Status of Cooling
Unavailable due to Control Mode
despite being above cooling
setpoint, or with a status of
Heating Unavailable due to
Control Mode despite being below
the setpoint.
The staged equipment shuts off
above the cooling setpoint or below
the heating setpoint when the PID
is running on the TEC. If the unit is
in On/Off Control mode, this does
not apply.
The staged equipment cycles too
rapidly or too slowly when the PID
is running on the TEC.
The controller provides an error
when trying to upgrade firmware.
The TEC3000 zone temperature
does not change fast enough
compared to the measured zone
temperature from a verification
device (a calibrated sensor).
TEC3000 Series On/Off or Floating Fan Coil and Individual Zone Thermostat Controllers with Dehumidification
1
(Part 1 of 2)
Probable Causes
The 2-pipe fan coil/VAV system
does not have a changeover
sensor and switch connected, or
the sensor/switch has failed.
The changeover temperature is
sensing a hot supply, but the
controller is requesting cooling.
Changeover temperature is
sensing a cold supply, but the
controller is requesting heating.
The Control Mode is set to
Cooling Mode, but the controller
is requesting heating.
The Control Mode is set to
Heating Mode, but the controller
is requesting cooling.
The PID control algorithm
minimizes overshoot and energy
usage for the particular
equipment and zone, and may
cycle the equipment prior to
reaching setpoint.
The control band around the
setpoint is determined by the
minimum on/off times and is set
incorrectly for the equipment,
zone, or user preference. There
is a tradeoff between reduced
control band size and increased
energy usage and equipment
wear from increased cycling.
The firmware on the USB drive is
below the minimum required
version.
Error code 1025.
The TEC3000 is configured by
default for larger spaces with
normal-sized equipment when a
proportional device is active.
Capability Installation Instructions
45
Solutions
1. Check the wiring of the supply temperature
sensor/switch.
2. Verify that the changeover is set up correctly
for the type of sensor attached (sensor or
switch).
1. Verify that the supply is not in heating mode. If
it is, nothing can be done from the TEC.
2. Check the wiring of the supply temperature
sensor or switch.
3. Check the placement of the supply
temperature sensor or switch.
4. Verify that the changeover is set up correctly
for the type of sensor attached (sensor or
switch).
1. Verify that the supply is not in cooling mode. If
it is, nothing can be done from the TEC.
2. Check the wiring of the supply temperature
sensor or switch.
3. Check the placement of supply temperature
sensor or switch.
4. Verify that the changeover is set up correctly
for the type of sensor attached (sensor or
switch).
Change the Control Mode to Auto or Heating.
Change the Control Mode to Auto or Cooling.
Expected behavior.
1. Verify that equipment minimum on/off times are
set correctly.
2. If the default deadband around the setpoint
does not provide the desired temperature
control, set Temp Control Setup to Deadband
Override and set the Deadband parameter to
the desired value.
Please use firmware version 3.0.2.xxxx or higher.
A reboot is required to clear the Firmware
Mismatch fault that occurs.
Select Control Setup >Tuning > Equipment Size
> Oversized.