Field Behaviour of Inverter Air Conditioners Effect on Seasonal Performance

ABSTRACT Considerable technological advancements in domestic air conditioner (AC) designs over the past few decades have seen substantial developments in the variable speed compressor (inverter) operation. Current test standards allow inverter AC (IAC) manufacturers to ‘lock’ the compressor speed for a desired ‘rated’ capacity. ViPAC Engineers & Scientists Ltd (ViPAC) believes rating the inverter under ‘locked’ mode is unrealistic, as it does not reflect the way inverters operate in real life operation. Testing IAC units showed input power deviation in ‘unlocked’ modes in contrast to when tested in the ‘locked’ mode for similar output capacity. In this study, the seasonal performance of two IAC units in cooling mode is compared using data collected from ‘laboratory’ and ‘field’ tests. The results show a large variance in the predicted outcome. Labelling according to field performance would value the performing units and possibly eliminate units with poor performance, which would ultimately benefit the end users. It is suggested that the design regime of temperature controls in IAC units be reviewed and that the ‘field’ test method be considered for IAC testing and labelling.