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This study aimed to evaluate cold water produced by chiller that will be distributed to the fan coil unit (FCU). The cold water distribution system from chiller requires good insulation, especially water pipes in and out of FCU to chiller so water temperature remains stable and chiller performance is not too heavy. Increasing temperature of cold water produced by chiller will affect the performance of the air conditioning system (AC) and the use of electrical energy. The object of this study is chiller unit with 18 FCU units located at the Bandung Electronic Center. Detailed measurements have been taken on the AC system. The results of thermodynamic analysis shows that there is a considerable comparison between the ideal heat loss and the actual heat loss, which is 131,972 kW for supply pipelines and 124,498 kW for return pipelines. Heat loss will also result in increased electricity consumption. The measurement and evaluation results showed the insulation of cold water distribution pipe is not effective enough because there are damaged parts of the insulation, the size or thickness of the insulation used does not match the size of the pipe causing unbalanced chilled water flow rate and heat loss. [ABSTRACT FROM AUTHOR]

This paper analyzes the performance of a water cooled chiller at various number of fan cooling tower under the constant cooling capacity. The nominal capacity of the water cooled chiller unit is 800.0 ton and the refrigerant is R-514A. The performance of the water cooled chiller system when using 6 fans with a COP of8.29 and a kW/TR value not exceeding the minimum value set under the ASHRAE standard of0.42. The largest energy consumption is generated when the system uses 3 fans which is 2513.58 kWh during the period of time the system is turned on (7 hours). While the lowest energy consumption is generated when the system uses 6 fans which is 2036.78 kWh during the period of time the system is turned on (7 hours). The percentage of energy consumption increase when using 6 fans to 5 fans by 12,78%, from 5 fans to 4 fans by 7.48 % and from 4 fans to 3 fans by I,79%. Based on the results of analysis of the use of fan cooling tower variations on the performance and energy consumption of water cooled chiller is best when using 6 fans. [ABSTRACT FROM AUTHOR]

Relatively, R32 has very low GWP compared to R22, and therefore leading R32 to be a potential substitute for R22. This paper investigates the performance changes due to drop-in replacement of R22 to R32 in a residential air conditioner. The liquid density ratio between R32 and R22 at 0°C is 0.82. As a result, theoretically, for drop-in 100% from R22 with R32, the refrigerant charge amount of R32 is 82% of R22 (by mass). In this experiment, the refrigerant charge mass of R32 is varied from 90% to 105% with 5% increment for each measurement. Experimental results show that the optimal refrigerant charge amount is 95%. At this optimal refrigerant charge amount, the mass ratio of R32 to R22 is 77.9%. Meanwhile, at this mass ratio, the cooling capacity increased by 7.7% and COP decreased by 12.1%. [ABSTRACT FROM AUTHOR]

This paper analyzes the performance of a split air conditioner at various condensing temperature under the constant cooling capacity. The nominal capacity of the air conditioning unit is 5.06 kW and the refrigerant is R-410a. The simulation shows that the increase of the condensing temperature causes the unit require the higher volumetric and mass flow rate of refrigerant to maintain the constant cooling capacity. The condenser capacity and the work of compression increase as well. On the other hand, the refrigerating effect decreases so that the overall performance of the air conditioning unit decreases. [ABSTRACT FROM AUTHOR]