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TRUE RESIDENTIAL
®
Testing the inverter board:
1.
Test for line voltage to the inverter. There should be 120V AC between black and orange wires. If no,
check wire harness.
2.
Test for signal from temp control board. There should be 120V AC on purple. If no, test the temp
control board.
Because of the frequency of the following voltage tests, not all multimeters may be capable of measuring the
correct voltage. These tests were made using a good quality multimeter, i.e. Fluke, U.E.I., and Amp Probe
brands. The voltage read by your meter will most likely not match the readings made with another meter. The
goal is to verify the presence of the drive signals.
3. Test for output voltage of the inverter board. With the leads still attached to the compressor and
your meter set for 200V AC, test for voltage between all the windings. If your meter reads 150V,
for example, between two windings, it should read 150V between all the rest of the terminals (see
example B). If it does not read same voltage at all three windings, suspect the speed board as being
faulty.
INVERTER BOARD DIAGNOS TICS TABLE
LED STATUS
LED STATUS DESCRIPTION
1 FL ASH
15 seconds
Normal operation
2 FL ASH
5 seconds
Control communication problem.
•
Pull down cycle - if inverter doesn’t sense
the thermostat signal for 10 minutes.
•
Normal cycle - if inverter doesn’t receive the
thermostat signal for 4 hours
3 FL ASH
5 seconds
VCC inverter problem.
•
Some problem on the inverter hardware
4 FL ASH
5 seconds
VCC compressor problem.
•
Is not possible to keep the speed over 1,600
rpm in an overload or overvoltage situation
•
Inverter is reaching the max power even at
the minimum speed (1,600 rpm)
•
Starting fail
•
Rotor position fail
•
Over 221ºF internal inverter temperature
1 FL ASH
Temperature protection activated.
•
Over 203ºF internal inverter temperature
•
Power limit decreases to protect the inverter
NOTE: PRIOR TO CONDEMING THE INV ERTER BOA RD. OHM THE COMPRESSOR OUT TO MA K E SURE IT 'S
NOT SHORTED TO GROUND NOR HAS AN OPEN WINDING.