TemperZone UC8 Troubleshooting Guide

Temperzone UC8 Troubleshooting Guide
Page 14 of 24
Display
Fault
Possible causes
Possible remedy
F22
F23
F24
F25
System 1 or BMS
serial comms lost
System 2 serial
comms lost
System 3 serial
comms lost
System 4 serial
comms lost
Loose wiring.
Repair connections.
Slave system or BMS controller off.
Turn master system or BMS on.
Slave system or BMS communications
intermittent.
Ensure BMS communicates at least
once every 5 minutes.
Electrical interference.
Use twisted pair screened cables.
Signals A and B must form a pair.
Connect screen to 0V at the UC8.
Re-route cables away from other
cabling where possible.
Incorrect DIP switch settings.
Check DIP switch settings.
F26
Cannot read DIP
switches
Moisture on controller circuit board.
Allow controller to dry.
Faulty controller.
Replace controller circuit board.
F27
Invalid fan
selection
Incorrect DIP switch settings.
Correct DIP switch settings.
Indoor unit not detected.
Ensure indoor unit powers up at
the same time, or before, the
outdoor unit.
Check connections with the indoor
unit.
F28
Missing outdoor
coil de-ice
temperature
sensor
Control signals request heating mode
on a cooling-only unit.
Remove heating mode request
signal.
Loose wiring.
Repair connections.
Faulty outdoor coil de-ice sensor.
Replace sensor.
F29
Microcontroller
temperature too
high
Wait until the unit has cooled down.
Find the cause of extremely high temperature in the electrical compartment.
F30
Supply voltage out
of bounds
Check that 230V AC mains power supply voltage is stable.
F31
A slave system
reports a fault
Check slave systems.
F32
Internal comms
problem
Moisture on controller circuit board.
Allow controller to dry.
Faulty controller.
Replace controller circuit board.
F33
Refer to “high discharge superheat” (HI-dSH)
F34
Problem with
readings from the
pressure
transducers
Transducer wires swapped.
Correct transducer wiring.
Transducers fitted to wrong pipe.
Swap transducers.
Incorrect transducer type.
Fit correct transducer.
Expansion valve closed.
Repair EEV wires.
Faulty transducer.
Replace transducer.
F35
Reverse cycle valve
Loose wiring.
Repair wiring.
Faulty reverse cycle valve.
Replace reverse cycle valve.
F36
Invalid DIP switch
setting on TZT-100
thermostat
Check TZT-100 thermostat DIP switch 4 is ON: The reverse cycle valve is ON
when the unit operates in heating mode.

TemperZone UC8 Specifications

General

Brand	TemperZone
Model	UC8
Category	Controller
Language	English