R407C를 적용한 인버터 열펌프의 용량조절 특성

An experimental study was performed on the characteristics of an inverter driven water-to-water heat pump system with a variation of compressor frequency and expansion devices. R22 and R407C were used as the working fluid, and the compressor frequency was altered from 30㎐ to 75㎐. Temperature of the secondary fluid entering condenser was varied as 30 ℃, 34 ℃, 39 ℃. The system using R407C had smaller COP decrease at a higher frequency. When R22 and R407C were applied to the same heat pump system, capacity and COP with R407C were lower than those with R22.