Daikin Mini-Split Code H0
Soft lockout
Compressor system sensor abnormality. Before the compressor starts, the DC current or DC voltage reading is out of range (current sensor output outside 0.5 to 4.5 V, or DC bus below 50 V), or the compressor draws no current at start-up.
Manual wording: “H0 Compressor system sensor abnormality”
Documented for: RKS/RXS pair outdoor units, FTXM-W/V outdoor units
Likely causes, most common first
- Broken or disconnected harness
- Disconnection of the compressor harness
- Disconnection of reactor
- Defective outdoor unit PCB
- Defective compressor
- Supply voltage obviously low or high
What you can safely check yourself
- Check the breaker or disconnect for the outdoor unit is fully on
- Turn the system off at the breaker or disconnect switch, wait a minute, and turn it back on once
When to call a technician
H0 means the outdoor board cannot see the compressor's current or voltage. Checking the reactor and compressor harness inside the outdoor electrical box is technician work.
A Daikin mini-split throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- Service Manual - Inverter Pair FTXS-L Series / FDXS-L Series (SiUS091133) (Daikin, FTXS09/12/15/18/24/30/36LVJU wall mount, FDXS09/12LVJU ducted, RKS/RXS09-36LVJU outdoor) · checked 2026-08-25
- Service Manual - Inverter Pair Wall Mounted Type H-Series (SiUS04-924_A) (Daikin, FTXS30/36HVJU indoor, RKS30/36HVJU and RXS30/36HVJU outdoor) · checked 2026-08-25
- Service Manual - Inverter Pair Wall Mounted Type FTXM-W/V Series (SiUS042113EA) (Daikin, FTXM-W / FTXM-V (Daikin Atmosphera) wall-mount heat pump) · checked 2026-08-25