5156631-UIM-G-0417
Johnson Controls Unitary Products
17
41
Phase Lost -
Detected by
Speed
Step 1.
Loose or incorrect wire connections.
Check incoming power leads, the leads to the compressor
plug, and the OD fan terminals.
Step 2.
Phase imbalance.
Check compressor winding resistance or miswire of compres-
sor leads at the compressor terminals and at the inverter drive.
2 Ton 0.88 Ohm
3 Ton 0.53 Ohm
4 Ton 0.44 Ohm
5 Ton 0.29 Ohm
W: Red Wire (RED).
V: Black Wire (BLK).
U: Brown Wire (BRN).
Step 3.
Inverter internal damage.
Change out the inverter drive. (Validate the fix. If the issue is
persistent, reinstall the original inverter drive, and go to step 4.)
Step 4.
Compressor internal damage.
Replace compressor. (Validate the fix. If the issue is persistent,
reinstall the original compressor, and go to the last step.)
Last Step.
If fault remains.
Contact JCI Technical Services
42
Phase Lost -
Detected by
Current
Step 1.
Loose or incorrect wire connections.
Check incoming power leads, the leads to the compressor
plug, and the OD fan terminals.
W: Red Wire (RED).
V: Black Wire (BLK).
U: Brown Wire (BRN).
Step 2.
Phase imbalance.
Check compressor winding resistance or miswire of compres-
sor leads at the compressor terminals and at inverter drive.
2 Ton 0.88 Ohm
3 Ton 0.53 Ohm
4 Ton 0.44 Ohm
5 Ton 0.29 Ohm
W: Red Wire (RED).
V: Black Wire (BLK).
U: Brown Wire (BRN).
Step 3.
Inverter internal damage.
Change out the inverter drive. (Validate the fix. If the issue is
persistent, reinstall the original inverter drive, and go to step 4.)
Step 4.
Compressor internal damage.
Replace compressor. (Validate the fix. If the issue is persistent,
reinstall the original compressor, and go to the last step)
Last Step.
If fault remains.
Contact JCI Technical Services.
43
Compressor IPM
Fault – By Rising
and
Falling Edges of
Insulated-Gate
Bipolar
Transistor (IGBT)
Voltage
Step
1. Verify the system has the correct amount
of refrigerant.
Refer to the Product Technical Guide.
Step 2.
Sudden supply voltage change.
Check supply voltage to the outdoor unit.
(If low or high, contact utility provider.)
(Inverter is not designed for use with a generator.)
(Brownout condition.)
(Check for a cut or damaged wire short to ground.)
Step 3.
Sudden load change on the fan motor.
Troubleshoot outdoor fan motor & blade.
(Ensure they are in good working order.)
Check fan harness and connectors.
Step 4.
Inverter internal damage.
Change out the inverter drive.(Validate the fix. If the issue is
persistent, reinstall the original inverter drive, and go to step 5.)
Step 5.
Compressor internal damage.
Replace Compressor.(Validate the fix. If the issue is persistent,
reinstall the original compressor, and go to the last step.)
Last Step.
If fault remains.
Contact JCI Technical Services.
TABLE 10:
Compressor Inverter Drive Fault (Continued)
INVERTER
FAULT
CODE
FAULT
DESCRIPTION
POSSIBLE CAUSES
ACTIONS
