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Heating and Heating and Air- Air- Conditioning Conditioning Chapter 37

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Chapter 37. Heating and Air-Conditioning. FIGURE 37.1 Water is a substance that can be found naturally in solid, liquid, and vapor states. FIGURE 37.2 The extra heat required to change a standard amount of water at its boiling point to a vapor is called latent heat of vaporization. - PowerPoint PPT Presentation

TRANSCRIPT

Page 1: Heating and Air-Conditioning

Heating and Air-Heating and Air-ConditioningConditioning

Chapter 37

Page 2: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.1 FIGURE 37.1 Water is a substance that can be found naturally in solid, liquid, and vapor Water is a substance that can be found naturally in solid, liquid, and vapor states.states.

Page 3: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.2 FIGURE 37.2 The extra heat required to change a standard amount of water at its boiling The extra heat required to change a standard amount of water at its boiling point to a vapor is called latent heat of vaporization.point to a vapor is called latent heat of vaporization.

Page 4: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.3 FIGURE 37.3 The latent heat of vaporization that water vapor stores is given off when The latent heat of vaporization that water vapor stores is given off when the vapor condenses to a liquid.The temperature stays the same.the vapor condenses to a liquid.The temperature stays the same.

Page 5: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.4 FIGURE 37.4 A sling psychrometer is used to measure relative humiditA sling psychrometer is used to measure relative humidit

Page 6: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.5 FIGURE 37.5 Typical flow of air through an automotive heat, ventilation, and air-Typical flow of air through an automotive heat, ventilation, and air-conditioning system when placed in the heat position. The air conditioning compressor conditioning system when placed in the heat position. The air conditioning compressor does not normally operate in the heat mode.does not normally operate in the heat mode.

Page 7: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.6 FIGURE 37.6 A typical heater core as installed in an HVAC What Is an Auxiliary Electric A typical heater core as installed in an HVAC What Is an Auxiliary Electric Water Pump? housing.Water Pump? housing.

Page 8: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.7 FIGURE 37.7 The evaporator removes heat from the air that enters a vehicle by The evaporator removes heat from the air that enters a vehicle by transferring it to the vaporizing refrigerant.transferring it to the vaporizing refrigerant.

Page 9: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.8 FIGURE 37.8 The compressor provides the mechanical force needed to pressurize the The compressor provides the mechanical force needed to pressurize the refrigerant.refrigerant.

Page 10: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.9 FIGURE 37.9 The condenser changes the refrigerant vapor into a liquid by transferring The condenser changes the refrigerant vapor into a liquid by transferring heat from the refrigerant to the air stream that flows between the condenser fins.heat from the refrigerant to the air stream that flows between the condenser fins.

Page 11: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.10 FIGURE 37.10 A typical air-conditioning system that uses an expansion valve. A A typical air-conditioning system that uses an expansion valve. A temperature sensor bulb is attached to the outlet of the evaporator to control the temperature sensor bulb is attached to the outlet of the evaporator to control the amount of refrigerant allowed to flow into the evaporatoramount of refrigerant allowed to flow into the evaporator

Page 12: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.11 FIGURE 37.11 A typical automotive air-conditioning system that uses a cycling clutch and A typical automotive air-conditioning system that uses a cycling clutch and an orifice tube.an orifice tube.

Page 13: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.12 FIGURE 37.12 Typical orifice tube.Typical orifice tube.

Page 14: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.13 FIGURE 37.13 A cutaway of an air-conditioning compressor electromagnetic clutch.A cutaway of an air-conditioning compressor electromagnetic clutch.

Page 15: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.14 FIGURE 37.14 R-134a is available in 12-oz cans as well as larger 30-lb containers.R-134a is available in 12-oz cans as well as larger 30-lb containers.

Page 16: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.15 FIGURE 37.15 A depletion of the ozone layer allows more ultraviolet radiation from the A depletion of the ozone layer allows more ultraviolet radiation from the sun to reach Earth’s surface.sun to reach Earth’s surface.

Page 17: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.16 FIGURE 37.16 Chlorofluorocarbon molecules break apart in the atmosphere.Chlorofluorocarbon molecules break apart in the atmosphere.

Page 18: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.17 FIGURE 37.17 The label on a Toyota Fuel Cell Hybrid Vehicle (FCHV) showing that CO2 is The label on a Toyota Fuel Cell Hybrid Vehicle (FCHV) showing that CO2 is being used as the refrigerant.being used as the refrigerant.

Page 19: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.18 FIGURE 37.18 The condenser serves the same function for both the orifice-tube and the The condenser serves the same function for both the orifice-tube and the expansion valve–type air-conditioning system, and that is to remove the heat from the expansion valve–type air-conditioning system, and that is to remove the heat from the refrigerant and cause the hot refrigerant vapors to condense into a hot liquid.refrigerant and cause the hot refrigerant vapors to condense into a hot liquid.

Page 20: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.19 FIGURE 37.19 A repaired condenser refrigerant line.A repaired condenser refrigerant line.

Page 21: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.20 FIGURE 37.20 The evaporator serves the same function for both the orifice-tube and the The evaporator serves the same function for both the orifice-tube and the expansion valve–type air-conditioning system, and that is to allow the liquid refrigerant expansion valve–type air-conditioning system, and that is to allow the liquid refrigerant to evaporate and absorb heat from the passenger compartment.to evaporate and absorb heat from the passenger compartment.

Page 22: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.21 FIGURE 37.21 Expansion-valve systems store excess refrigerant in a receiver-drier, which Expansion-valve systems store excess refrigerant in a receiver-drier, which is located in the high-side liquid section of the system, whereas orifice-tube systems is located in the high-side liquid section of the system, whereas orifice-tube systems store excess refrigerant in an accumulator located in the low-side vapor section of the store excess refrigerant in an accumulator located in the low-side vapor section of the system.system.

Page 23: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.22 FIGURE 37.22 A typical accumulator used on a cycling clutch orifice-tube (CCOT) system.A typical accumulator used on a cycling clutch orifice-tube (CCOT) system.

Page 24: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.23 FIGURE 37.23 Rigid lines and flexible hoses are used throughout the air-conditioning Rigid lines and flexible hoses are used throughout the air-conditioning system. The line to and from the compressor must be flexible because it is attached to system. The line to and from the compressor must be flexible because it is attached to the engine, which moves on its mounts during normal vehicle operation.the engine, which moves on its mounts during normal vehicle operation.

Page 25: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.24 FIGURE 37.24 A typical expansion valve which uses an inlet and outlet attachment for A typical expansion valve which uses an inlet and outlet attachment for the evaporator, and a temperaturesensing bulb that is attached to the evaporator the evaporator, and a temperaturesensing bulb that is attached to the evaporator outlet tube.outlet tube.

Page 26: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.25 FIGURE 37.25 A slot cut in the ball seat inside the expansion valve permits a small A slot cut in the ball seat inside the expansion valve permits a small amount of refrigerant and oil to pass through at all times, even when the valve is amount of refrigerant and oil to pass through at all times, even when the valve is closed. This flow of oil through the system is necessary to make sure that the closed. This flow of oil through the system is necessary to make sure that the compressor receives the oil it needs for lubricationcompressor receives the oil it needs for lubrication

Page 27: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.26 FIGURE 37.26 The sensing bulb is attached to the evaporatoroutlet tube. Refrigerant The sensing bulb is attached to the evaporatoroutlet tube. Refrigerant inside the bulb expands or contracts in response to the evaporator temperature.inside the bulb expands or contracts in response to the evaporator temperature.

Page 28: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.27 FIGURE 37.27 Pressure from the capillary tube pushes on the spring-loaded diaphragm to Pressure from the capillary tube pushes on the spring-loaded diaphragm to open the expansion valve. As the pressure in the capillary tube contracts, the reduced open the expansion valve. As the pressure in the capillary tube contracts, the reduced pressure on the diaphragm allows the valve to close.pressure on the diaphragm allows the valve to close.

Page 29: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.28 FIGURE 37.28 An H-valve (H-block) combines the temperature- sensing and pressure-An H-valve (H-block) combines the temperature- sensing and pressure-regulating functions into a single assembly.regulating functions into a single assembly.

Page 30: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.29 FIGURE 37.29 An H-valve as used on a Chrysler minivan.An H-valve as used on a Chrysler minivan.

Page 31: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.30 FIGURE 37.30 In this Chrysler system, a low-pressure cutoff switch and a cycling-clutch In this Chrysler system, a low-pressure cutoff switch and a cycling-clutch switch are mounted on the Hvalve.switch are mounted on the Hvalve.

Page 32: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.31 FIGURE 37.31 The orifice tube is usually located at the inlet tube to the evaporator.The orifice tube is usually located at the inlet tube to the evaporator.

Page 33: Heating and Air-Conditioning

chapter 37 Heating and Air-Conditioning

FIGURE 37.32 FIGURE 37.32 This hybrid vehicle A/C compressor uses two scrolls; one being belt-driven This hybrid vehicle A/C compressor uses two scrolls; one being belt-driven (left) and the other driven by a brushless DC motor (right).(left) and the other driven by a brushless DC motor (right).