Daikin · Heat pumps · Daikin Altherma 3 R F (split heat pump, R32)
L5-00OU: Inverter instantaneous overcurrent (DC)
Name in the manufacturer's documentation (service manual): OU: Inverter instantaneous overcurrent (DC)
[1]
In plain words (editorial)
Instantaneous DC overcurrent in the outdoor unit's inverter. The manual names a closed stop valve or clogged refrigerant circuit, or a faulty inverter or main PCB.
When to call a service technician: Contact your installer or Daikin dealer.
✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.
For technicians
Possible causes (source text)
Steps given by the manufacturer (source text)
⚠ Work on refrigerant circuits, mains electricity and PV DC wiring is for qualified technicians only.
The Polish page has more detail (plain-language explanation, safe checks, guides): Read in Polish →
Sources
Every statement has a footnote to the document and PDF page. “Quote verified” means the quote was found automatically in the text of that page.
- [1] Daikin Altherma 3 R F – ERGA04~08E + EHVH/X04+08S18+23E – Installer reference guide (4P629086-1D (2024.04)) , p. 255 official manufacturer document quote verified
L5-00 OU: Inverter instantaneous overcurrent (DC)
- [2] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
closed stop valve in the refrigerant circuit.
- [3] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
clogged refrigerant circuit.
- [4] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
faulty inverter pcb.
- [5] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
faulty main pcb.
- [6] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
check that all stop valves of the refrigerant circuit are open.
- [7] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
check if the refrigerant circuit is clogged.
- [8] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
perform a check of the inverter pcb.
- [9] Daikin – Service manual Daikin Altherma 3 R F + W, ESIE20-13C – 2022.09 (PDF copy on installer site cncpompyciepla.pl) (ESIE20-13C) , p. 56 manufacturer document – copy from a distributor quote verified
perform a check of the main pcb.