1. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Bad case of Installation RAC-B-A07

2. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Causes : Effects : 1.Customer requirement due to less budget. 2.Not calculate cooling load. Insufficient Cooling Capacity 1.Not cool. 2.Lots of power consumption. 3.Compressor operates all the time. 4.Short lifetime of compressor.

3. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Causes : 1.The unit,9000BTU/hr, is installed in the big room which has more excessive heat load than its cooling capacity. Effects : 1.Less efficiency. 2.Not cool enough. 3.Much electric consumption. Excessive Cooling Load

4. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Excessive Cooling Load Cloth partitionHair streamer Causes : Effects : 1.Cool air leakage due to low insulated material partition. 2.Heat generation of electric appliances e.g. streamer, iron, and drier, etc. 1.Less efficiency. 2.Not cool enough. 3.Much electric consumption. 4.Supply stream air in case of lots of humidity in the room. Hot air leakage through net window above the unit

5. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Water Drop Due to Condensation Causes : Effects : 1.Too much moisture content in the conditioning room. 1.Water condensed at the surface of flap and the bottom of base. 2.Water dropping damages the electric appliance beneath or the wood floor.

6. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. To air conditioner Causes : Effects : 1.Cost saving of electric wiring. 2.Lack of safety knowledge on circuit breaker installation. 1.Hazard to life during service work. Electric Shock Bad connection

7. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. To air conditioner Electric Shock Good connection IN OUT

8. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Faulty Electric Wiring Causes : Effects : 1.Over electrical load than on the other electric appliances. 1.Over withstand limits on the conductor. 2.Over thermal energy than thermal rating of cord’s insulation. 3.Short lifetime of electric cord.

9. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Connect neutral wire to the terminal of communication signal. Wrong Communication Wiring 1.Damaged electronic devices in the communication circuit of PWB. 2.The system cannot operate due to no communication signal between indoor and outdoor. Causes : Effects :

10. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Short Circuit Board Causes : Effects : 1.Improperly apply cement over the drain hole. 1.Some small animals such as mouse or lizard enter into PWB. 2.Electric wiring is bitten by rat. 3.PWB is shorted.

11. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Poor Insulating Work Causes : Effects : 1.Poor covering insulation. 2.Not cover through the long pipe run. 1.Water condensed drops to stain the ceiling or wall. 2.Less efficiency.

12. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Refrigerant Leakage Causes : Effects : 1.Poor flaring copper pipe. 2.Scratches on the copper tubing flare or on the brass flare fitting 1.No cooling. 2.Compressor is gradually damaged in case of the long run period with less refrigerant amount. 3.Increase global warming and ozone depletion.

13. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Causes : Effects : 1.Broken flare nut due to too much torque application to fasten flare nut. 1.No cooling. 2.Compressor is gradually damaged in case of the long run period with less refrigerant amount. 3.Increase global warming and ozone depletion. Refrigerant Leakage

14. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Causes : Effects : 1.Less upper space left caused less return air flow. 1.Poor heat transfer resulted in less efficiency. 2.No superheat caused compressor failure. 3.Loud noise of air flow. 4.Difficult to take off the front panel because no space enough to unlock above the unit. Less Return Air flow

15. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Less Return Air flow

16. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Returned Cool Air Flow Causes : Effects : 1.Obstruction of wind would force the cool wind back the return grille. 1.Less efficiency and poor heat transfer. 2.Frequent cutting-off of compressor. 3.Not cool enough. 4.Less super heat. 5.Liquid back caused mechanic wear for long run operation.

17. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Less Ventilation and Short Air Circulation Causes : Effects : 1.Less side space around the outdoor unit caused less return air flow. 1.Poor heat transfer and no sub-cool resulted in less efficiency. 2.High discharge temperature. High pressure of both sides with high current. 3.Compressor failure in case of the long run period. 4.Loud noise of air flow. 5.Difficult to take off the front panel because no space enough to do service work.

18. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Poor Ventilation Causes : Effects : 1.No space to install outdoor units caused poor hot air ventilation. 1.Poor heat transfer and no sub-cool resulted in less efficiency. 2.High pressure of both sides and high current caused compressor stop. 3.Compressor is gradually damaged in case of the long run period. 4.Loud noise of air flow. 5.Cumulative heat amount. 6.Difficult to do service work.

19. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Poor Ventilation - Hot Air Blow

20. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Poor Ventilation - Hot Air Blow

21. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Poor Ventilation - Hot Air Blocked

22. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Short Air Circulation and Hot Air Blow

23. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Bad installation design space For outdoor unit

24. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Rattling Noise Causes : Effects : 1.Step on top panel when installation of outdoor unit. 1.Much noise of vibration occurred by hitting among the following metal parts during system operation run. - Top panel - Front panel - Motor bracket - Baffle plate - Left & right side panel 2.Annoyance of neighbors in the night time.

25. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Causes : Effects : 1.Installation of outdoor unit to the wooden wall. 1.Much noise of vibration annoys end-user and neighbors in the night time. Vibration Noise

26. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Vibration Noise Causes : Effects : 1.Installation of outdoor unit on the metal roof. 1.Much noise of vibration annoys end-user and neighbors in the night time.

27. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Vibration Noise Causes : Effects : 1.Indoor unit is improperly locked to installation board. 1.Much noise of vibration occurred by hitting between installation board and plastic base during system operation run. 2.Annoyance of end user in the night time.

28. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Less Space for Service Work Causes : Effects : 1.No area for service work. 1.Difficult to connect electric wire securely to the terminal block and possibly heat up at the connection caused fire. 2.Difficult to connect firmly gas and liquid side pipes by Torque wrench and possibly leak out the refrigerant caused cooling problem.

29. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Less Space for Service Work Causes : Effects : 1.No area for service work. 1.Difficult to open the top panel to change PWB.

30. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Out of Control by Remote Control Causes : Effects : 1.IR Receiver is interfered by directly lighting of fluorescent lamp. 1.Out of control by remote control. 2.Lots of power consumption. 3.Compressor operates for a long time before normal stop. 4.Plastic part color is changed.

31. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. Many point of brazing pipe are not accept.

32. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. 1.Normal condensation from cold refrigerant pipes inside outdoor unit. Causes : Effects : 1.Dropped water would damage the electric appliance below. Connection pipe need between 2 holes Condensed Water from Outdoor Unit Condensed water tray

33. © 2012 MITSUBISHI HEAVY INDUSTRIES – MAHAJAK AIR CONDITIONERS CO., LTD. All Rights Reserved. End Thank you!