Presently Rental office is famous in downtown that near food center and have good transportation. In Thailand office buildings usually have operating time 8-10 hours per day. So need to improve the building for energy conservation and employee’s comfort. Glasses are one way that heat transfers occur highly. Overall Thermal Transfer Value (OTTV) is a tool for measure heat transfers through building envelope. From OTTV calculation for existing building OTTV is 92.94 W/m2 that over ministerial regulations indicate 50 W/m2. Improving building envelope by add more thickness of glasses can reduce OTTV 1.3% and improving building envelope by film installation can reduce OTTV 47.2% and improving building envelope by add shading can reduce OTTV 48.5%. However each improving policy have each investment cost. Conjoint analysis is consider of many factor to find willingness to pay for each choice. So set policies for energy conservation water and waste management and increase comfort are employees to improve energy conservation water and waste management and increase comfort are 19935.90 17590.50 and 1563.60 baht respectively so can improve building envelope by add shading result in OTTV to 47.8 W/m2 Budget 18000 Baht can be improve organization that payback about 5400 Baht per year. Increase thermal comfort by install table fan. From the result of research expect to apply to improve rental office in the future.

Currently transport has played an important role in everyday life resulting in huge traffic jams caused by big city streets and pollution problems from global warming to global temperatures are rising. Since humans are creatures that prefer comfort in all areas which contrasts with the higher temperatures of the Earth. Currently the use of air conditioning a lot. To modify the temperature is reduced in the range 2 3 to 25 degrees Celsius makes people feel comfortable. However the use of air conditioning in the car cabin cooling efficiency can be increased to a higher level than it is by cooling the refrigerant. The aim of this research is to test and compare the performance of car air conditioning systems usually equipped with a heat exchanger. Using water from the condensation of evaporator as a medium for heat transfer. By installing the equipment at the outlet of the condenser. This causes the temperature of the refrigerant is low. The pipe lengths in the equipment from the calculation of 1 .2 meters and copper lines that increases the length of the tubes was calculated to compare with a length of 1.6 meters to test the speed of the compressor 1000 1500 2000 and. 2500 rpm and a wind speed of 20 35 and 50 kilometers per hour. The results of experiment found that the temperature refrigerant equipment decreased from an average of 1.6 degrees Celsius the pipe length of 1.2 meters and 1.6 meters of pipe temperature drops 1.8 degrees average temperature attended Eva sufficiently reduced operator. It increases energy efficiency ratio averaged 6.68% of the pipe length 1.2 m and 22.24% at a length of 1.6 meters as well as to increase the coefficient of performance of the air conditioning system. 6 .6 9 % of the pipe length of 1.2 meters and a length of 1.6 meters at 22.4% with the key factor in optimizing the cars air conditioning system. Making the refrigerant from the condenser the temperature drops to pull heat out of the cabin through evaporator higher.

Now a day the mostly air condition are use vapor compression refrigeration system in which R-22 refrigerant is used as a working substance. From the results of study it found that the quantity of water vapor or moisture in the air is condensed with in the fan coil unit while through out the evaporator. The fluid after condense is called condensed water. By this process the quantity of condensed water is increases when the air condition is used in the long time. To increase the utility the condensed water is recovered for the heart reduction in the finned-tube condenser. The experiment is consist of two conditions by using the air and condensed water to heart reduction. But in case of condensed watcr the pressure openation is controlled at 280 and 260 Psig respectively. The results of efficicncy ratio (EER) is 39675 Btu/hr 3.01 and 10.3 Btu/hr Watt respectively with the air is used At the pressure operation 280 Psig refrigeration effect (C.O.P) and (EER) is 44212 Btu/hr 3.38 and 11.5 Btu/hr. Watt respectivecly and 49856 Btu/hr 3.99 and 13.6 Btu/hr Watt at pressure operation 260 Psig. Furthermore the capacity of condenser is increases to 11.43% and 25.6% and also the refrigerant efficient is increases to 12.43 % and 32.43% at the pressure operation 280 and 260 Psig. Thus the pararneter of energy efficiency ratio depends on the capacity of condenser working substance temperature (pressure operation) and air surrounding tcmperature.

Now a day the mostly air condition are use vapor compression refrigeration system in which R-22 refrigerant is used as a working substance. From the results of study it found that the quantity of water vapor or moisture in the air is condensed with in the fan coil unit while through out the evaporator. The fluid after condense is called condensed water. By this process the quantity of condensed water is increases when the air condition is used in the long time. To increase the utility the condensed water is recovered for the heart reduction in the finned-tube condenser. The experiment is consist of two conditions by using the air and condensed water to heart reduction. But in case of condensed water the pressure operation is controlled at 280 and 260 Psig respectively. The results of experiment shown the refrigeration effect coefficient of performance (C.O.P) and energy efficiency ratio (EER) is 39675 Btu/hr 3.01 and 10.3 Btu/hr.Watt respectively with the air is used. At the pressure operation 280 Psig refrigeration effect (C.O.P) and (EER) is 44212 Btu/hr 3.38 and 11.5 Btu/hr.Watt respectively and 49856 Btu/hr 3.99 and 13.6 Btu/hr.Watt at pressure operation 260 Psig. Furthermore the capacity of condenser is increases to 11.43% and 25.6% and also the refrigerant efficient is increases to 12.43% and 32.43% at the pressure operation 280 and 260 Psig. Thus the parameter of the energy efficiency ratio depends on the capacity of condenser working substance temperature (pressure operation) and air surrounding temperature.

Defrosting at evaporator panel is one of working cycles in freezer. Power consumption in defrosting does not meet the objective of using freezer therefore the approach to decrease power consumption in defrosting is one strategy for energy saving. Normally the cycle of defrosting in freezer is a constant time that specify by referring to the highest humidity period. With this control concept the problem of temperature exchange is not occurred from ice accumulation at evaporator panel but it makes the over necessity of defrosting process in the low humidity season and cause the unnecessary power usage in freezer. This research presents the control approach for defrosting by using the difference of the temperature at evaporator and the temperature at chilling area. By using this approach the defrosting process is operated depend on load and the fan is on or off relate to defrosting time. Test results demonstrate that about 12% of power can be saved by this control approach when compared to constant time control.