Multi-Zone Outdoor Condenser Installation Manual
DURASTAR.COM26
TROUBLESHOOTING
When troubles occur, please check the following points before contacting a repair company.
PROBLEM POSSIBLE CAUSES SOLUTION
Poor Cooling 
Performance
Temperature setting may be higher 
than ambient room temperature
Lower the temperature setting
The heat exchanger on the indoor 
or outdoor unit is dirty
Clean the affected heat exchanger
The air filter is dirty Remove the filter and clean it according 
to instructions
The air inlet or outlet of either unit is 
blocked
Turn the unit off, remove the obstruction 
and turn it back on
Doors and windows are open Make sure that all doors and windows are
closed while operating the unit
Excessive heat is generated by 
sunlight
Close windows and curtains during 
periods of high heat or bright sunshine
Low refrigerant due to leak or long-
term use
Check for leaks, re-seal if necessary and 
top off refrigerant
Excessive heat is generated by 
sunlight
Excessive heat is generated by sunlight
Too many sources of heat in 
the room (people, computers, 
electronics, etc.)
Reduce amount of heat sources
Poor Heating 
Performance
The outdoor temperature is
extremely low
This model is designed to work down to 
-13°F, however, heating performance is 
impacted at temperatures below freezing
Cold air is entering through doors 
and windows
Make sure that all doors and windows are 
closed during use
Low refrigerant due to leak or
long-term use
Check for leaks, re-seal if necessary,
and top off refrigerant
The unit 
starts and 
stops fre-
quently
There’s too much or too little 
refrigerant in the system
Check for leaks and recharge the system 
with refrigerant
Incompressible gas or moisture has 
entered the system
Evacuate and recharge the system with 
refrigerant
The compressor is broken Replace the compressor
The voltage is too high or too low Install a manostat to regulate the voltage










