Troubleshooting guide

OM 931-3 / Page 13 of 28
Figure 6: MicroTech III Unit Controller LED Status and Faults Troubleshooting Reference
Flash Yellow LED
Read Outputs
Check Timers
Brownout
High
Pressure
R - W 1
R -Y 1
Flash Green LED
Stop Compressor
No
Yes
No
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Low
Pressure
Low Suct
Temp Sensor
Low Suct
Temp
Room Temp
Sensor Failure
Condensate
Overflow
Stop Compressor
Flash Red LED
Stop Compressor
Flash Yellow LED
Flash Green LED
Solid Red LED
Stop Compressor
Heating Mode
Run in Cooling
Mode for 1 Min.
No
Yes
Cooling Mode
Turn on
Yellow LED
Stop Compressor
Reversing
Valve On
Time Delay
Start
Compressor
30 Second
Time Delay
Request for
Water Flow