Hitachi Yutaki fault 8
Excessively high discharge gas temperature at the top of compressor
Heat pumpWhat it means
Cycle abnormality where discharge gas temperature at the top of compressor is excessively high.
Likely causes
- Insufficient refrigerant charge
- Refrigerant leakage
- Expansion valve closed or clogged
Where to start
- Check which compressor icon(s) are active to determine which refrigerant circuit compressor is currently running (S80 units)
- For S80, confirm whether R410A (1) or R-134a (2) compressor circuit is enabled
- Check Water Outlet PHEX Temperature
The full answer, free
- 16 more checks in order
- The readings and component tests from the manual
- The manual page for this fault (page 85), right under the answer
Safety: Isolate the outdoor unit and any backup heater, and give the inverter capacitors time to discharge before you open the electrics. Anything on the refrigerant circuit needs F-gas certification.
From the Hitachi manual for the Yutaki. Check the model on the data plate before you order parts.