Trane · Heat pump

L5 Lockout: drive AC input over-current

High severity Trane 5TWR7

What the control is telling you

Repeated input 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

Supply voltage out of range
Voltage drop from loose or undersized wiring
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.
Measure incoming line voltage under load; compare with the nameplate range.
Check the disconnect, breaker and wire size for voltage drop.
Tighten all line connections at 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

H5 Hard lock: drive AC input over-current
H6 Hard lock: high drive IPM temperature
H7 Hard lock: high drive PFC temperature
H8 Hard lock: high coil temperature
L6 Lockout: high drive IPM temperature
L7 Lockout: high drive PFC temperature
L8 Lockout: high coil temperature
FA Outdoor ambient sensor fault

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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.