Midea Error Code PC42: Compressor start failure (Heat Pump)

Updated October 13, 2026 · by Aurora Star Tech Inc.

Midea error code PC42 on a heat pump means: Compressor start failure. It is also called Midea diagnostic code PC42.

High severityHeat PumpMidea DLCURA ducted single-zone inverter heat pump (outdoor)

Homeowner? What Midea code PC42 means for you

Call a technician Your heat pump is reporting: Compressor start failure. The heat pump has locked out or cannot run properly. One reset is fine; if the code comes back, it needs a licensed technician to find the cause.

Safe things you can check yourself

Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
Check both breakers and the outdoor disconnect box beside the outdoor unit; all should be ON.
Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
In winter, keep snow and ice off and away from the outdoor unit. A short defrost cycle with steam is normal.
Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.

Call (647) 657-2977 Book a service call

Licensed technicians serving Vaughan, Toronto and the GTA.

What does Midea error code PC42 mean?

The compressor failed to start.

Applies to: DLCURAH18-60 AAK/ABK single-zone heat pump outdoor units (18K-60K, regular and High Heat)

Common causes of Midea code PC42

Loose/incorrect compressor U-V-W wiring
Low supply voltage
Compressor locked or winding fault

A technician checks these and 2 other possible causes on site before replacing any part.

Safety: Gas, electrical and refrigerant work must be done by a licensed technician. Turn off power and gas before servicing, never bypass a safety control, and always follow the manufacturer's manual for your exact model.

Midea models that use code PC42

DLCURAH18AAK DLCURAH18ABK DLCURAH24AAK DLCURAH24ABK DLCURAH30AAK DLCURAH30ABK DLCURAH36AAK DLCURAH36ABK DLCURAH48AAK DLCURAH48ABK DLCURAH60AAK DLCURAH60ABK

Other Midea Heat Pump codes

Code	Meaning
PC10	Outdoor low AC voltage protection
PC11	Outdoor DC bus high voltage protection
PC12	DC bus high voltage protection / 341 MCE error
PC30	System high pressure protection
PC31	System low pressure protection
PC40	Main chip to compressor-driver chip communication error
PC43	Compressor lack-phase protection
PC44	Outdoor unit zero-speed protection
PC45	Outdoor IR chip drive failure
PC46	Compressor speed out of control
PC49	Compressor over-current failure
PH90	Evaporator high temperature protection

All Midea Heat Pump error codes →

Midea code PC42: homeowner questions

What does Midea code PC42 mean?

Compressor start failure. The compressor failed to start.

Is it safe to keep using my heat pump with code PC42?

It depends on the cause. The heat pump has locked out or cannot run properly. One reset is fine; if the code comes back, it needs a licensed technician to find the cause.

Can I reset Midea code PC42 myself?

You can try one reset (power off for 30 seconds, then on). If Midea code PC42 comes back, the cause is still there and a licensed technician should check it.

Who can fix Midea code PC42 near me?

Aurora Star Tech Inc. repairs Midea heat pumps in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.

Homeowner help: AC Running But Not Cooling: What to Check · Heat Pump Not Heating or Blowing Cold Air

Source: Midea/Carrier DLCURA Installation Instructions (Catalog DLCURA-03SI), Table 11 Outdoor Unit Diagnostic Codes, p.19. Written in our own words as a summary; always check the original manual.

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.