HITACHI Mini-Split Air Conditioner Outdoor Unit RAC-S25X Inverter Compressor Running Sound

I disassembled a Hitachi air conditioner outdoor unit, RAC-S25X, removed the sound-absorbing material, and recorded the compressor operation sound. Although not as loud as the RAC-S40X2 that we recently published, this model has a low carrier frequency at startup, and the startup sound is reminiscent of IGBT-VVVF on a train. The motor sound heard after the change to a higher carrier frequency is also slightly train-like. RAC-S40X2 →    • HITACHI Mini-Split Air Conditioner Outdoor...   The compressor's rpm does not go up much, perhaps because the compressor's elimination volume is too large for its capacity, but the buzz that becomes noticeable in the mid-speed range and beyond is like that of a Hitachi scroll. (3:32) ☆☆☆Air conditioner information ☆☆☆ Manufacturer ：HITACHI Model ：RAC-S25X Capacity(Cooling) ：2.5kw Voltage ：100V Frequency ：50/60Hz Year of manufacture ：2008 Compressor ：Scroll (HITACHI EU1013E1) Refrigerant ：R410A Mass ：36kg ☆☆☆About this channel[○ ]☆☆☆ Thank you for watching my channel!^^ I am a Japanese air conditioner enthusiast. This channel mainly posts japanese air conditioner running videos, disassembled running videos, running sounds, etc. You can enjoy the running videos of air conditioners that are rich in individuality depending on the manufacturer and age. If you like it, please subscribe to My channel. ↓Below is a playlist of videos by genre, so please take a look.↓ ☆☆☆Playlist☆☆☆ Indoor Unit →   • Indoor Units Video エアコン室内機シリーズ   Outdoor Unit →   • Outdoor Units Video エアコン室外機シリーズ   Fan Spinning →   • Outdoor unit propeller fan spinning video ...   Compressor sound(attention the volume) →   • Attention to Volume⚠️  Compressor direct s...   Outdoor unit running sound→   • 三菱電機のマルチエアコン室外機 MXZ-6017AS 冷房時の運転音 Noise o...   Defrost operation→   • 【霜取り運転】三菱エアコン ズバ暖霧ヶ峰 室外機 MUZ-KXV2818 霜取り運転...   Gas Heat Pump air conditioner→   • 【室外機運転音】三菱重工ガスヒートポンプエアコン(GHP)室外機 始動音～運転音 S...   ☆☆☆About me☆☆☆ ・Twitter   / aircon_kousuke   ・Instagram   / aircon_kousuke