Trane · Heat pump

LC Lockout: compressor over-current

High severity Trane 5TWR7

What the control is telling you

Repeated compressor over-current caused a lockout. Manual lists only the meaning (A1000BA board); steps are general checks drawn from other sections of the guide.

Applies to: Trane 5TWR7 multi-speed heat pump (5TWR7024A-060A)

Likely causes

Low or high supply voltage
Loose compressor wiring
Charge problem or closed service valve
Dirty coil / poor airflow
Compressor or drive fault

Test and repair steps

Warning: After power off, wait 2 minutes - the inverter can hold 400 VDC. Confirm under 42 VDC at the +DC/-DC test points before touching the board.
Confirm supply voltage at the unit matches the nameplate.
Check compressor wiring and terminals at the drive for looseness or burn marks.
Verify refrigerant charge by subcooling and that both service valves are fully open.
Check outdoor coil is clean and airflow unrestricted.
If it repeats with good voltage and charge, check compressor windings and the drive.

Settings for these units

Outdoor unit placement · Trane 5TWR7

Item	Value
Above unit	5 ft clear
Service side	3 ft
Walls / shrubs	12 in. min
Pad	1 in. larger than unit all round, level, separate from house
Cold climate (HP)	raise 3-12 in. above pad
Within 1 mile of salt water	add BAYSEAC001 if no factory salt shield
Operating range	cooling 55-120 F, heating 0-66 F

Avoid bedroom walls and under roof drip lines.

Dimensions and weights · Trane 5TWR7

Model	H x D x W (in.)	Weight (lb)
5TWR7024A	41 x 30 x 33	181
5TWR7036A	41 x 30 x 33	194
5TWR7048A	41 x 34 x 37	231
5TWR7060A	41 x 34 x 37	241
5TTR7024A	41 x 30 x 33	176
5TTR7036A	41 x 30 x 33	189
5TTR7048A	41 x 34 x 37	226
5TTR7060A	41 x 34 x 37	236

Weights are estimated, uncrated.

Models that show this code

4 models in Trane 5TWR7

5TWR7024A5TWR7036A5TWR7048A5TWR7060A

Other codes on the same units

HF Hard lock: outdoor fan over-current
HH Hard lock: high pressure (HPCO / DTC)
HL Hard lock: low pressure (LPCO)
Hd Hard lock: high discharge temperature
LF Lockout: outdoor fan over-current
LH Lockout: high pressure (HPCO / DTC)
LL Lockout: low pressure (LPCO)
Ld Lockout: high discharge temperature

Save it for the next call

Star this code in the HVACopedia app and keep the whole library on your phone for jobs with no signal.

Open the app

Source: Trane ODR-SVN002E-EN (5TTR7/5TWR7 installer's guide) - section Integrated Variable Speed Control Board LED Indicators, Table 18 (A1000BA models). Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.