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Steps for DLS Troubleshooting
If error is already displayed, make note of it. If Multi-Zone check 
each Indoor Unit for error. If no error displayed, wait up to 5 
minutes for error to reappear. Some errors are constant retry 
and will only appear every 3 to 5 minutes to display again. 
During this time either a normal display or an “88” will be seen.
If the system is a Multi-Zone 38MGR36 or 48 go to the 
outdoor unit and pull the last error code from the Main PCB. 
Procedure is towards the back of this guide. After code is 
retrieved go to next step.
Recycle power and try system again. Give the system a 
minimum of 10 minutes for error to appear again.
If error appears again, go to the flow chart for the error 
displayed and work the error.
Things to check during any troubleshooting service call.
• Power to the units? Within limits?
• All wire harness connected and fully seated in their 
sockets?
• Is the end user operating the system correctly?
• Raise or lower the set point (Heat vs. Cool) 5 or more 
degrees, wait 10 minutes, system come ON?
On Multi-Zone systems, operate each zone independently first. 
Check Heating & Cooling if temperature permits. This will help 
rule out cross piping and wiring. Even if the system has been 
installed for some time, still check this. It is often missed at the 
time of start up.