Samsung mini split error code E404
Outdoor overload protection (heating).
- TypeProtection
- SystemRefrigerant circuit
- Can I fix it?Homeowner checks, then maybe a tech
What E404 means on a Samsung
In heating mode the system is working beyond its limits (pressures too high) and stopped to recover. Usually restricted indoor airflow.
On this platform, E404 is a protection: the system stopped or throttled itself to prevent damage; many clear on their own once conditions return to normal.
Common causes
- Dirty filters or a dirty indoor coil.
- The indoor fan running slow.
- An overcharge.
How to fix it yourself
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician.
- Pull the front panel and check the filters and the indoor coil. Dirty filters and a matted coil restrict airflow, and airflow problems trigger a surprising number of protection codes.
- Reset the system: switch the breaker (or the outdoor disconnect) off, wait a full five minutes so the boards fully discharge, then switch it back on and restart from the remote.
Switch off power at the breaker before opening either unit. Capacitors in the outdoor unit hold a charge for several minutes after power is cut.
When to call a technician
Persistent E404 with clean filters needs a technician.
Which Samsung units show E404
This page applies to Samsung Wind-Free, Quantum, Max Heat and Free Joint Multi units. Samsung's own documentation lists E404 as "Outdoor overload protection (heating)", the same definition used across the Samsung it is built on. If your unit shows a code with a different shape (for example a four-character code, or a plain number), it is from a different table; use the lookup with your exact code.
Where Samsung shows this code
The indoor display shows E followed by three digits (E101, E554). Units without a full display blink the indicator lamps in a pattern the manual decodes; the outdoor board's 7-segment display or LEDs show the same code. E1xx codes are indoor-unit faults, E2xx are communication faults, E4xx are outdoor sensors, protections and inverter faults, and E5xx are outdoor board and refrigerant faults.
Other Samsung codes
Same part of the system as E404:
Questions people ask
Can I reset a Samsung E404 code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If E404 comes back, the fault is real and needs the checks above.
Is it safe to keep running a Samsung showing E404?
Not repeatedly. A protection code means the unit stopped itself to prevent damage, and resetting it over and over can turn a cheap repair into a compressor failure. Reset once, check the basics, and stop if it returns.
Do I need a technician for Samsung E404?
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician. Persistent E404 with clean filters needs a technician.
Sources
- Samsung residential split service manuals (error code tables)
Updated September 2026. Codes and definitions vary by model year. If your manual disagrees with this page, your manual wins. Send a correction.