TemperZone UC8 Troubleshooting Guide

Temperzone UC8 Troubleshooting Guide
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11. Fault messages
Display
Meaning
Possible causes
Possible remedy
LP
Low pressure
protection
Check for refrigerant leaks.
Fix leak, evacuate unit, then recharge.
Expansion valve (EEV) is
closed.
Check valve coil is properly fitted onto the valve
body.
Check UC8 DIP switch settings.
Repair wiring to the valve.
Replace expansion valve.
Faulty transducer cable.
Faulty transducer.
Faulty LP switch.
Repair transducer cable.
Replace transducer.
Replace LP switch.
Service valve is closed.
Open service valves.
Indoor fan does not start
(cooling mode) or
outdoor fan does not start
(heating mode).
Repair fan wiring.
Replace fan.
Incorrect DIP switch settings.
Change DIP switch settings then restart the
controller.
HP
High pressure
protection
Outdoor fan does not start
(cooling mode) or
indoor fan does not start
(heating mode).
Repair fan wiring.
Replace fan.
Unit is overcharged.
Remove excess refrigerant charge.
EEV is closed.
Check UC8 DIP switch settings.
Repair wiring to the expansion valve.
Replace expansion valve.
Faulty transducer cable.
Faulty transducer.
Faulty HP switch.
Repair cable to the transducer.
Replace transducer.
Replace HP switch.
Service valve is closed.
Open service valves.
Incorrect DIP switch settings.
Change DIP switch settings then restart the
controller.
HI-t
High
temperature
protection
Insufficient refrigerant.
Add refrigerant.
Faulty discharge line
temperature sensor.
Replace sensor.
Incorrect DIP switch settings.
Change DIP switch settings then restart the
controller.
FROSt
Indoor coil
frost
protection
Air filter blocked.
Clean or replace air filter.
Dampers closed.
Check dampers and damper controls.
Excess amount of cold fresh
air introduced.
Check fresh air damper and damper controls.
Indoor fan speed too low.
Increase indoor fan speed.
Faulty indoor fan motor.
Faulty indoor fan speed
controller.
Replace indoor fan motor.
Replace indoor fan speed controller.
Return air temperature too
low.
Ensure unit is not operated in cooling mode
with very low return air temperature.
Insufficient refrigerant.
Add refrigerant.

TemperZone UC8 Specifications

General

Brand	TemperZone
Model	UC8
Category	Controller
Language	English