HVACopediaTrane · Heat pump
F1 Compressor start-up fault
What the control is telling you
Compressor failed to start properly. 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
Other codes on the same units
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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.