Fujitsu · Heat pump
Outdoor LED1 11 flashes Indoor unit capacity error (outdoor board LED)
What the control is telling you
Multi-zone 18/24 outdoor board: LED1 flashes 11 times while the other LEDs stay off. Same fault family as indoor code 22. The LEDs sit on the back side of the board and are seen through a hole.
Applies to: Fujitsu 18 type (2-zone) and 24 type (3-zone) multi outdoor units
Likely causes
- Wrong indoor sizes for this outdoor / multi combination
- Main PCB fault
Test and repair steps
- Look at the outdoor PCB LEDs (rear of the board, viewed through the hole) and count the flashes on each LED.
- Then follow the checks for indoor code 22: Add up the indoor capacities and compare with the allowed range and combination table of the outdoor unit.
- Correct the selection.
- If the combination is right, replace the main PCB.
Settings for these units
Operating range and service space · Fujitsu multi-zone outdoor 18/24 type
| Item | Value |
|---|---|
| Cooling outdoor range | 14 to 115 F DB |
| Heating outdoor range | 5 to 75 F DB |
| Cooling indoor range | 65 to 90 F DB |
| Heating indoor range | 60 to 88 F DB |
| Rear (open top, rear wall only) | 4 in. or more |
| Rear + sides | 4 in. rear, 10 in. sides |
| Front wall only | 24 in. or more |
| Between side-by-side units | 10 in. or more |
| Base height | 2 in. or more above floor |
Unit tilt no more than 3 degrees and never toward the compressor side.
Below 32 F outdoor do not fit the drain pipe/caps (freezing).
Other codes on the same units
- Outdoor LED1 1 flash Serial comms error, outdoor to indoor unit A (outdoor board LED)
- Outdoor LED1 10 flashes High pressure switch 2 error (outdoor board LED)
- Outdoor LED1 12 flashes Overcurrent trip detection (outdoor board LED)
- Outdoor LED1 13 flashes Compressor rotor position detection error (outdoor board LED)
- Outdoor LED1 14 flashes Trip terminal L error (outdoor board LED)
- Outdoor LED1 15 flashes Outdoor fan motor error (outdoor board LED)
- Outdoor LED1 17 flashes Outdoor PCB micro communication error (outdoor board LED)
- Outdoor LED1 18 flashes High discharge temperature (outdoor board LED)
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.
Source: Fujitsu Outdoor unit 18-24 type (North American trilingual) installation P-N 9374747160.pdf - section 8.2 Outdoor unit LED. 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.