Cooper & Hunter mini split error code U7
Four-way (reversing) valve fault.
- TypeFault
- SystemRefrigerant circuit
- Can I fix it?Technician job
What U7 means on a Cooper & Hunter
The reversing valve that switches between heating and cooling did not change over as commanded, or the coil temperatures do not match the mode selected.
On this platform, U7 is a fault: something has failed or is disconnected and needs diagnosis.
Common causes
- A stuck reversing valve.
- A failed reversing valve solenoid coil or its wiring.
- Low refrigerant charge (the valve needs a pressure difference to shift).
- A coil sensor reading wrong.
How to fix it yourself
Do the reset and the visual checks, but the underlying repair needs a technician with a meter and the service manual.
- 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 between Cool and Heat and listen for a whoosh at the outdoor unit as the valve shifts.
- With power off, check the small solenoid coil plug on the reversing valve is seated.
- Anything inside the refrigerant circuit (sensors are fine, but valves, compressors and leaks are not) needs EPA-certified refrigerant handling. That is a technician job.
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
Valve replacement is a brazing and recharge job for a technician.
Which Cooper & Hunter units show U7
This page applies to Cooper & Hunter Sophia, Astoria, Olivia, Dakota, Hyper Heat, Alice and MIA units. Cooper & Hunter's own documentation lists U7 as "Four-way (reversing) valve fault", 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 U7:
U7 on other brands
The same characters do not always mean the same thing. Check the brand on your unit.
- Blueridge U7 Four-way (reversing) valve fault
- Mitsubishi Electric U7 Superheat abnormal (discharge temperature too low)
Questions people ask
Can I reset a Cooper & Hunter U7 code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If U7 comes back, the fault is real and needs the checks above.
Is it safe to keep running a Cooper & Hunter showing U7?
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.
What will a technician check for U7?
Valve replacement is a brazing and recharge job for a technician. Ask for the measurements, not just a parts quote.
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.