Uncertainty analysis of air conditioner performance measurement based on liquid secondary refrigerant method

Based on the liquid secondary refrigerant method and the uncertainty theory of indirect measurement parameters, the calculation model of standard uncertainty of air conditioner performance parameters is established. The evaluation method of standard uncertainty of performance measurement parameters based on the liquid secondary refrigerant method is given. As an example, the evaluation of standard uncertainty of integrated part load value（IPLV） for water-cooled chillers is analysed. The results show that the standard uncertainty introduced from inlet and outlet water temperature measurement has greater influence on IPLV, followed by water flow and power measurement factors. The type A measurement standard uncertainty of IPLV is much less than the type B measurement standard uncertainty. Therefore, it is necessary to focus on the accuracy of instruments when measuring the IPLV of water-cooled chillers. The higher accuracy of instruments can effectively reduce the measurement uncertainty of performance parameters of water-cooled chillers.