Cooper & Hunter mini split error code C5
Jumper cap malfunction (missing or wrong jumper).
- TypeFault
- SystemControl board
- Can I fix it?Homeowner checks, then maybe a tech
What C5 means on a Cooper & Hunter
Gree indoor boards use a small plug-in jumper that tells the board which model it is. The board cannot find it, or it is the wrong one. This almost always happens after a board replacement or a service visit.
On this platform, C5 is a fault: something has failed or is disconnected and needs diagnosis.
Common causes
- The jumper was left off after board work.
- The wrong jumper was installed.
- The jumper's socket is corroded or damaged.
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.
- With power off, open the indoor electrical box and look for a small plug-in jumper on the main board (often labelled JUMP).
- Reseat it firmly. If the board was replaced, move the jumper from the old board to the new one.
- 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
If the jumper is present and seated, the board needs a technician's attention.
Which Cooper & Hunter units show C5
This page applies to Cooper & Hunter Sophia, Astoria, Olivia, Dakota, Hyper Heat, Alice and MIA units. Cooper & Hunter's own documentation lists C5 as "Jumper cap malfunction (missing or wrong jumper)", the same definition used across the Gree platform 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 Cooper & Hunter shows this code
The code shows on the indoor unit's display in place of the temperature. If the display is off, press the Light button on the remote. Some models also count out the code as indicator blinks. E codes are system protections and faults, F codes are mostly sensor faults, H codes are outdoor and compressor protections, U codes are motor and valve faults, and P codes are power-supply faults.
Other Cooper & Hunter codes
Same part of the system as C5:
C5 on other brands
The same characters do not always mean the same thing. Check the brand on your unit.
- Blueridge C5 Jumper cap malfunction (missing or wrong jumper)
- Daikin C5 Indoor heat exchanger (gas pipe) temperature sensor fault (open or short circuit)
Questions people ask
Can I reset a Cooper & Hunter C5 code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If C5 comes back, the fault is real and needs the checks above.
Is it safe to keep running a Cooper & Hunter showing C5?
The unit will usually refuse to run, or run with reduced output, until the fault is cleared. Repeated resets do not fix anything and can mask a problem that is getting worse.
Do I need a technician for Cooper & Hunter C5?
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician. If the jumper is present and seated, the board needs a technician's attention.
Sources
- Cooper & Hunter error code list and owner's manuals
- Gree residential split service manuals
Updated September 2026. Codes and definitions vary by model year. If your manual disagrees with this page, your manual wins. Send a correction.