23 September 2011
Recently, performance of insulation and air tightness for residential house has
been improved in cold region. Therefore, heating load remains at low level through most of
heating period. Inverter controlled heat pump is effective appliance to improve efficiency on
partial load condition, but it is pointed out that COP operated in low load less than 1kW is not
high due to on-off operation. To solve these problems, we make a prototype room airconditioner with inverter-controlled dual compressor which is tuned to low heating load in low
outside temperature. We measure COP in various conditions, and conduct the field test to
clarify whether prototype room air-conditioner can provide excellent COP in low load.
Measured COP on field test is 2.6.