Daikin Mini-Split Code H8
Soft lockout
DC voltage or current sensor abnormality on 09/12 class units, or CT (current transformer) or related abnormality on 24/30/36 class units. The compressor is running above about 32 Hz but the sensed input current is implausibly low.
Manual wording: “H8 DC voltage / current sensor abnormality (09/12 class only) / CT or related abnormality (24/30/36 class only)”
Documented for: RKS/RXS pair outdoor units, FTXM-W/V outdoor units
Likely causes, most common first
- Defective outdoor unit PCB
- Defective power module
- Broken or disconnected wiring
- Defective reactor
What you can safely check yourself
- Turn the system off at the breaker or disconnect switch, wait a minute, and turn it back on once
When to call a technician
The manual's own remedy for H8 is replacing the outdoor unit PCB after current measurements. That is a technician job.
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