1. ALL OR NOTHING A simple look at Domestic Air-conditioning

2. An air conditioner (often referred to as AC or air con) is an appliance, system, or machine designed to change the air temperature and humidity within an area typically using a refrigeration cycle but sometimes using evaporation, commonly for comfort cooling in buildings and motor vehicles.appliancesystem machinerefrigeration cycleevaporation There may even be a heating cycle.

3. In 1902, the first modern electrical air-conditioning unit was invented by Willis Haviland Carrier in Buffalo, New York, after graduating from Cornell University.inventedWillis Haviland CarrierBuffalo, New YorkCornell University

4. SPLIT - TYPE

6. 1 piece WINDOW - TYPE

11. Squeezing gas causes it to get HOT, lowering the pressure causes it to COOL. *** Hot air rises - cooling air falls. *** Hot air can hold a lot of moisture. Cold air cannot hold as much moisture.

12. Squeezing a gas causes it to get HOT Lowering the pressure causes it to COOL

15. Where should you place the two parts of a SPLIT – TYPE air-con? First the outside unit. (Condenser)

16. The air-con will probably be used at night in a bedroom. Do NOT place the outside unit under the window!

17. Try not to place in direct mid-day sun. Try to place on a solid wall with no window.

19. After all this, place as close to the inside unit as possible. The shorter the pipe, the better the result.

20. Where should you place the inside unit of a SPLIT – TYPE air-con? There are two types of indoor unit, WALL & FLOOR. (Evaporator)

21. Hot air rises Cooling air falls

22. De-Humidifying The art of drying air

23. Hot air can hold a lot of moisture. Cold air cannot hold as much moisture.

24. SPLIT - TYPE

25. If you blow hot, wet air against a cold metal box the air cannot hold the moisture and it will fall as water. Where does the water go?

26. SPLIT - TYPE

27. Two pipes carry gas to and from the indoor unit. One pipe carries the water from the moist air to the outside world

28. SPLIT - TYPE

29. If indoor unit is out of reach, a remote control is required. These days they can be very complex with many useful cycles of operation.

30. If long periods of inactivity occur, run air- con for about 10 mins every 3 or 4 weeks. Any rubber or synthetic material will degrade over time and can cause gas to escape. NO GAS = NO WORK!

31. Later Air-conditioners use a more complex compressor control unit Inverter Controlled Compressor Motors This allows a variable motor speed and a variable temperature cold-box. Much better control of temperature. More expensive.

32. The first air conditioners and refrigerators employed toxic or flammable gases, such as ammonia, methyl chloride, or propane, that could result in fatal accidents when they leaked. refrigerators ammoniamethyl chloride propane

33. The first non-flammable, non-toxic chlorofluorocarbon gas, Freon, in 1928.Freon ChlorofluorocarbonChlorofluorocarbon (CFC) Hydrochlorofluorocarbon (HCFC) Hydrofluorocarbon (HFC) refrigerantHCFC Hydrofluorocarbon DuPont

34. Squeezing gas causes it to get HOT, lowering the pressure causes it to COOL. *** Hot air rises - cooling air falls. *** Hot air can hold a lot of moisture. Cold air cannot hold as much moisture.

35. Why ALL OR NOTHING

36. THE END Pictures supplied by Wikipedia Inc