Mini split error codes, decoded
Find the code on your indoor unit, see what it means, work through the safe checks, and know exactly when the repair belongs to a technician.
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Mini-split brands
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Try a highlighted reference, or search for the exact code on your unit.
- Bosch · E0Bosch Mini Split E0 Error Code: Causes & Fixes (2026)E0 means an indoor unit EEPROM parameter error on Bosch Climate 5000 systems - the indoor (or outdoor) PCB main chip is not receiving valid feedb…
- Bosch · E1Bosch Mini Split E1 Error Code: Causes & Fixes (2026)E1 means a communication error between the indoor and outdoor units on Bosch Climate 5000 systems - the indoor control received no feedback from …
- Bosch · E3Bosch Mini Split E3 Error Code: Causes & Fixes (2026)E3 means an indoor fan speed error on Bosch Climate 5000 systems - the indoor fan did not run at the speed the control expected, so the system st…
- Bosch · E4Bosch Mini Split E4 Error Code: Causes & Fixes (2026)E4 means an indoor return-air temperature sensor error on Bosch Climate 5000 systems - the room temperature thermistor (T1) circuit is reading ou…
- Bosch · F0Bosch Mini Split F0 Error Code: Causes & Fixes (2026)F0 means outdoor current overload sensed on Bosch Climate 5000 systems - the current-detection circuit saw an abnormal current rise, often from a…
- Bosch · F6Bosch Mini Split F6 Error Code: Causes & Fixes (2026)F6 means an indoor coil outlet temperature sensor error on Bosch Climate 5000 Gen 2 / legacy single-zone systems - the T2B evaporator coil outlet…
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How to use this site
Find your brand above, then match the code or letter-number combination shown on your indoor unit's display or the remote's error screen. Each code page gives a quick answer first, then ranks the likely causes from most to least common, marks which checks are safe to do yourself, and tells you the exact point to hand off to a licensed technician — so you never pay for a repair call over something a filter cleaning would have fixed.