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Viessmann · Mini-split

LC06 IPM high temperature / PFC frequency limit

Medium severity Viessmann Vitocal 200-S DLCM(R/H)B multi-zone outdoorViessmann DLFSHB high wall indoor

What the control is telling you

Outdoor manual: IPM module overheat protection. Indoor manual: compressor speed limited because of the PFC. Check which applies by the unit's behaviour (stop vs slow-down).

Applies to: DLCM(R/H)B multi-zone outdoor units with DLFSHBH high wall indoor units (Midea, Carrier, Viessmann)

Likely causes

  • IPM heat sink loose / no thermal paste
  • Electric box mounted wrong

Test and repair steps

  1. Safety kill power at the disconnect and wait for the inverter capacitors to discharge before touching boards or wiring.
  2. Check the IPM heat sink screws are tight.
  3. Check the thermal paste under the IPM re-apply if missing or uneven.
  4. Check the electric control box is mounted right so air reaches the heat sink.
  5. Still faulty replace the IPM board.

Models that show this code

12 models in Viessmann Vitocal 200-S DLCM(R/H)B multi-zone outdoor, Viessmann DLFSHB high wall indoor

DLCMHBH24CAKDLCMHBH30DAKDLCMHBH36DAKDLCMHBH48EAKDLCMRBH18BAKDLCMRBH36DAKDLCMRBH48EAKDLFSHBH09XAKDLFSHBH12XAJDLFSHBH12XAKDLFSHBH18XAKDLFSHBH24XAK

Other codes on the same units

  • LC01 Speed limited by condenser temperature
  • LC02 Speed limited by discharge temperature
  • LC03 Speed limited by current
  • LC05 Speed limited by voltage
  • LH00 Speed limited by indoor coil temperature
  • LH07 Speed limited by remote
  • P0 Inverter module (IPM) fault
  • P1 Over or under voltage protection

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Source: DLCMRBH/DLCMHBH Multi-Zone Outdoor Service Manual (sold as Midea, Carrier and Viessmann Vitocal 200-S; Viessmann doc 6225551-03, 12/2024), Table 23 Outdoor Unit Error Display p.26; diagnosis p.44; Carrier MS-DLFSHB-01 High Wall Ductless Service Manual (04/2021), Table 9 p.17. 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.