INTRODUCTION
As the Coefficient of Performance (COP) of heat pump devices varies significantly according to the heating and cooling load and ambient temperature, when selecting a suitable device, it is very important to consider the thermal performance of the house and the local weather conditions. It is common to select a home-use air conditioners according to the room floorage in Japan. The heating and cooling load value per unit floorage from 1964 has not been revised, and is still used in the case of the present air-conditioner selection (maximum heating load per floorage: 275 W/m2). However, this is not the best method for highly insulated houses and leads to problems for energy conservation.
In this study, we developed a calorie meter to carry out temperature adjustment, and used it in analysis of the relationships among COP, heating and cooling load and outside air temperature. COP Matrix is constructed by a database of the measurement results. Furthermore, heat load calculation was performed using the insulation efficiency and the local condition of detached housing as analysis variables. As a result of the heat load calculation, Annual Performance Factor (APF) in actual environmental conditions is computed through correlation with the created COP Matrix. The APF calculated from experiment results is compared with the catalogue APF in order to clarify the characteristics of home-use air-conditioners considering the local conditions and heat load conditions.
RESEARCH METHODS
The indoor chamber of the calorie meter is 3 m wide, 3 m deep, and 2.7 m high. The outdoor chamber is 2 m wide, 2 m deep, and 2 m high. One temperature and humidity sensor and one thermistor anemometer are installed in the inlet of the inside air conditioner unit. Two temperature-and-humidity sensors are installed in the outlet of the inside air conditioner unit. One temperature-and-humidity sensors are installed in the inlet of the outside air conditioner unit, the temperature at this point is the outside temperature. Furthermore, in order to examine experimental accuracy, two thermocouples are separately installed in the inlet and three thermocouples are separately installed in the outlet of the inside air conditioner unit.
A COP matrix is created from the relationship of COP, heating and cooling load and outside air temperature. In order to consider the change of APF calculated from experiment results, analysis was performed by changing the insulation efficiency according to the Standard Model issued by the Architectural Institute of Japan (AIJ). We used the meteorological data of the AIJ extended AMeDAS meteorological data. Analysis was performed by heat load simulation software TRNSYS. COP was calculated by collation with the computed COP matrix.
RESULTS
The COP of cooling is lower when output is relatively low. The COP of heating is higher when the outdoor air temperature is relatively high. And there is a tendency for COP to rise as the flow rate of the inside unit increases. COP matrix in automatic flow rate is similar to COP matrix in relatively small flow rate.
Although the APF of an air conditioner in the catalogue is 5.6, which computed from COP matrix in case1-1 (Tokyo) is 2.9, which is about 0.5 times rather than catalogue value. The year cumulative power consumption in the catalogue is about 2,000 kWh, which computed from COP by the COP matrix in case1-1 (Tokyo) is about 3,200kWh, which is about 1.6 times rather than catalogue value.
The APF of heating and cooling become lower when insulation efficiency is relatively high. Because the heating load and cooling load is reduced, the frequency of the ON-OFF operation which COP is relatively low is increased.
