Heating & Climate Control MG Rover Group Heating & Climate Control

Heating & Climate Control Day One Introduction And Pre - Course Test. Air Conditioning Definition. Air Conditioning Physics. Air Conditioning System Components. The Differences In Refrigerants. The Flow Of Refrigerant In An Air Conditioning System. Safety Precautions When Handling Air Conditioning Systems.

Heating & Climate Control Day Two Reclaiming, Evacuation And Charging Air Conditioning Systems. Air Conditioning System Diagnostics And The Equipment Used. ATC Common Components And The Basic System Operation. Rover 25 & 45 Systems Rover 75 HEVAC & ATC End Of Course And End Test.

Standard Heating System 1 Front Face Level Outlet 2 Windscreen and Side Windows Outlet 3 Heater Assembly Casing 4 Air Inlet 5 Blower 6 Heater Matrix 7 Rear Footwell Outlet 8 Front Footwell Outlet 9 Heater Bypass Outlet

Rover 25 Standard Heater 1. Blower Unit 2. Heater Duct 3. Heater Unit 4. Blower Switch 5. Face Level Air Flow Control 6. Air Temperature Control 7. Recirculated Air Supply Control 8. Air Distribution Control

Rover 25 Heater Circuit

What Is Air Conditioning? Air Circulation Humidity Control Air Purification Temperature Control

What Is Humidity ? The Level Of Water Moisture In The Air Is Partially Dependent On The Temperature Of The Air . So The Feel Of Humidity Will Also Be Dependent On The Temperature. Measured In % 20Kg of Air at 30*C Can Hold 1Kg of Water If It Holds 900g Humidity is 90%

Humidity

Disadvantages ! Reduction Of Engine Power Increase Of Fuel Consumption Environmentally Unfriendly Gas The Vehicle Costs More To Produce, So The Customer Has To Pay A Premium For It

Advantages ! Improved Temperature Control Improved Quality Of Air Reduction Of Humidity Some Air Conditioning Systems Automatically Adjust For Different Ambient Conditions

How Is Temperature Measured? Degrees Centigrade ( C ) Degrees Fahrenheit ( F ) Kelvin ( K ) Degrees Rankine ( R )

Measurements Of Temperature C K F R

What is Latent Heat? The Amount of Energy Applied to or Removed From a Substance in Order for It to Change State

Four Changes Of State Liquefying Solid - Liquid Evaporation Liquid - Gas Condensation Gas - Liquid Solidification Liquid - Solid

Evaporation

Energy Used For State Change 0 To 100 C 100 C Liquid To 100 C Gas 418 KJ/KG 2248 KJ/KG

Factors Which Influence The Rate Of Evaporation The Type Of Substance. The Temperature Of The Substance. The Temperature Of The Substance Surroundings. The Pressure Acting On The Substance And Surroundings.

Measurements Of Pressure 1 Bar ~ 14.7 Psi 1 Bar ~ 100,000 Pascal Or 100 Kpa 1 Bar ~ 1 Kg/cm2 1 Bar ~ 760mm/hg

Effects of Pressure on Refrigerant

Methods of Heat Transfer Radiation Conduction Convection Forced Convection

Method Of Heat Movement By Radiation Light Bulbs Infra Red Heating Lamps Sun Light Micro Waves Radiation

Method Of Heat Transfer By Conduction Oil Circulating Around An Engine. Coolant To Radiator Fins. Coolant To Cylinder Block Or Head. Exhaust Gas To Exhaust Pipe. Heated Rear Or Front Window.

Methods Of Heat Transfer By Convection Radiator With A Fixed Or Electric Fan Interior Heating Matrix Engine Compartment Cooling The Movement Of The Vehicle Through The Air

Components Of An Air Conditioning System Compressor Condenser Receiver Dryer TXV Valve

Components Of An Air Conditioning System Evaporator Various Switches Fans

Compressor Types Scroll Type Vane Type Swash Plate Type Wobble Plate Type

Compressor 1 Pulley 2 Clutch connector 3 Inlet connection 4 Outlet connection 5 Control valve vent

Sectioned Compressor (swash plate type) 1 Clutch and pulley assembly 2 Shaft 3 Guide pin 4 Outlet port 5 Inlet port 6 Control valve assembly 7 Ball valve 8 Push rod 9 Diaphragm 10 Suction valve 11 Discharge valve 12 Piston 13 Swash plate 14 Lug plate A = Inlet pressure; B = Outlet pressure; C = Servo pressure; D = Ambient air pressure

Swash Plate Type

Compressor (Vane Type)

Vane Type Intake Phase

Vane Type Compress Phase

Vane Type Expel Phase

Scroll Type Operation

Wobble Plate Type

Condenser 1 Modulator 2 Desiccant 3 Filter 4 Plug 5 Heat exchanger 6 Outlet connection 7 Inlet connection 8 End tank

Receiver Dryer

Five Functions Of A Receiver Dryer Reservoir For The Refrigerant Remove Gas Bubbles Remove Moisture And Acids Filter Out Particulate Location For Sight Glass

Sight Glass Diagnosis Clear System OK or Empty Foamy Refrigerant Low or Contaminated With Air Streaky Refrigerant Low Cloudy Receiver/Dryer Broken & Contaminated System

TXV Valve Outlet Inlet Diaphragm Chamber Diaphragm Equaliser Circuit (Internal Type) Pressure Spring Capillary Tube Valve Equaliser Sensing Tube

Block Type TXV 1 Diaphragm 2 Housing 3 Metering Valve 4 Inlet Passage to Evaporator 5 Outlet Passage From Evaporator 6 Temperature Sensitive Tube

Evaporator

Evaporator Temperature Sensor

Refrigerant Flow 1.Compressor 2.Condenser 3.Receiver Drier –Integral To the Condenser on Rover 75 4.Thermostatic Expansion Valve 5.Evaporator 6.Flow Into Compressor 7.Blower Motor 8.Cooling Fan 9.Cooling Air Flow

Rover 75 System With Sub Cooler 1.Compressor 2.Condenser 3.Receiver Drier –Integral To the Condenser on Rover 75 4.Thermostatic Expansion Valve 5.Evaporator

Advantages of a Sub Cooler Improved System Performance Cost Reduction Weight Reduction Reduction in Power Consumption Reduction in Refrigerant Charge Quantity (Cost Saving) Less Joints in the System (Better Reliability – Less Chance of Leakage)

Trinary Switch

Typical Trinary Switch Working Pressures Stage 1 = Below 2 Bar - Switches Off 2.3 Bar Reinstates Stage 2 = 19 Bar Increase Fan Speed Stage 3 = Above 27 Bar - Switches Off 21 Bar Reinstates

System Safety Cut-outs Engine RPM Too Low – ECM Engine RPM Too High – ECM System Pressure Too Low – Trinary Switch System Pressure Too High – Trinary Switch Pressure Relief Valve

Air Conditioned System 1 Front Face Level Outlet 2 Windscreen and Side Windows Outlet 3 Heater Assembly Casing 4 Air Inlet 5 Blower 6 Evaporator 7 Heater Matrix 8 Rear Footwells Outlet 9 Rear Face Level Outlet 10 Front Footwells Outlet 11 Heater Bypass Outlet

Properties Of Refrigerant Have A Fast Change Of State Is Not Explosive Or Flammable Is Not Poisonous To Humans Long Shelf Life Is Not Corrosive To System Components

Dichlorodifluoromethane Refrigerant Type R12 R12 Dichlorodifluoromethane Chroloroflorocarbon Chlorine Fluorine Boiling Point -28.9C Carbon

Refrigerant Type R 134a R 134a Tetrafluoroethane Hydroflurocarbon Hydrogen Fluorine Boiling Point –26.5C Carbon

Ozone Protection June 1974 University Of California March 1985 United Nations Environmental Plan ( U N E P ) 1987 Montreal Protocol Identified Five Kinds Of Freon That Were Subject To Regulations Freon 11, 12, 113, 114, 115 1989 Vienna Treaty Total Abolition By 2000

Good Working Practices Protective Sealing Plugs Must Remain In Position, Assembly. If Caps Are Removed Or Damaged It Should Not Be Fitted And Returned. Always Use A Backing Spanner. Discard Opened Containers Of Oil After 1 Month. All Fixings Should Be Tightened To Their Correct Torque Settings.

Good Working Practices If the System Is Found Empty or Open the Receiver Dryer Must Be Replaced If There Is No Expulsion of Gas When Sealing Caps Are Removed the Compressor Must Be Replaced New ‘O’ Rings Must Be Fitted Upon Assembly New Components Must Be Allowed to Reach Room Temperature Before Fitment

Safety Precautions ! Wear Full Safety Goggles Wear Safety Gloves Know Where The First Aid Kit Is Located No Smoking

Recovery Procedure Reclaim Evacuate Recharge Test

Testing The System The Engine Rpm At Approx. 1500rpm The AC Inlet Temperature Of At Least 30 - 35 C The Heater Unit Settings, Set To Maximum Cooling And Fan Speed Also At Maximum, Doors Open.

Normal System Low Side 1.5 to 2.5 bar High Side 10 to 15 bar

Poor Efficiency Low Side 0.5 To 1.5 Bar High Side 6.0 to 8.0 Bar Suspect :- Under-charged(if Pipes Appear Frosted – Suspect Blocked or Clogged System)

Erratic Readings Low side 0.5 to 2.5 erratic High side 7.0 to 15 bar erratic Suspect :- Moisture in system

Intermittent Operation Low side 2.0 to 3.0 bar High side 20.0 to 25.0 bar Suspect :- Overcharged system

Poor Efficiency Low side 4.0 to 6.0 bar High side 8.0 to 10.0 bar Suspect :- Faulty compressor

Pipe Frosting Low side 2.0 to 3.0 bar High side 20.0 to 22.0 bar Suspect :- Sticking TXV valve

Rover 25 System Layout 1. Evaporator 2. Thermostatic Expansion Valve 3. High Pressure Servicing Connection 4. Receiver/drier 5. Condenser 6. Compressor 7. Low Pressure Servicing Connection

Rover 45 K Series Layout 1. Compressor 2. Low pressure servicing connection 3. Evaporator 4. Thermostatic expansion valve 5. High pressure servicing connection 6. Receiver/drier 7. Condenser

Rover 45 Diesel System Layout 1. Compressor 2. Low pressure servicing connection 3. Evaporator 4. Thermostatic expansion valve 5. High pressure servicing connection 6. Receiver/drier 7. Condenser

Rover 45 KV6 Layout 1. Compressor 2. Low pressure servicing connection 3. Evaporator 4. Thermostatic expansion valve 5. High pressure servicing connection 6. Receiver/drier 7. Condenser

Rover 75 Layout 1 Low pressure servicing connection 2 High pressure servicing connection 3 Refrigerant lines 4 Evaporator and thermostatic expansion valve 5 Condenser 6 Compressor

ATC System Inputs External Temperature Sensor Heater Coolant Temp Sensor Interior Temperature Sensor Evaporator Temp Sensor

ATC System Inputs Sunlight Sensor Feedback Potentiometer Driver Control Switches K-Bus

ATC Component Layout 1 In-car temperature sensor 2 ATC ECU 3 Heater coolant temperature sensor 4 Power transistor 5 Evaporator temperature sensor 6 Sunlight sensor 7 Trinary pressure switch

ATC System Outputs Heater Blower Fan Control Air Conditioning Request Blend Motors

ATC System Outputs Directional Motors Display Functions K-Bus

ATC Control Diagram 1 Heater coolant temperature sensor 2 Sunlight sensor 3 RH temperature servo motor 4 Distribution servo motor 5 ABS modulator 6 LH temperature servo motor 7 Instrument pack 8 Fresh/Recirculated air servo motor 9 BCU 10 Power transistor 11 Blower 12 Blower relay 13 In-car temperature sensor 14 ATC ECU

Heater Blower Control 31 Speeds in Automatic Mode 6 Speeds in Manual Mode ( 3,8,14,19,25 & 31) Blower Disabled in Auto Mode If Below -15ºC Blower Limited to Speed 3 in Auto Mode If Between -15ºC & 20ºC

Heater Blower Control When Cooling, Blower Purges Ducts for 5 Seconds at Speed 3 When Switched on – Progressing to Full Speed Within 6 Seconds On Reaching Selected Temperature Blower Reduces & Stabilises at 5 Steps Solar Heating Correction Raises Blower Speed by 6 Steps When Face Vents Selected

Heater Blower Correction Blower Speed Reduced by 8 Steps Between 25 & 60 Mph Blower Speed Increased by 8 Steps Between 60 & 25 Mph

Heated Rear Window Operation Ambient Air Temperature Below 10ºC – Engine Started – Auto on for 20 Mins Manually Switched on – Below 10ºc – on for 20 Mins Manually Switched on – Above 10ºc – on for 12 Mins

ATC Switch Pack & ECU

ATC ECU Self Diagnosis Carried Out Every Ignition Cycle Audible Bleep 3 Times (sunlight sensors disabled) Auto Window on Display Flashes for 20 Secs Reverts to Default Settings

Default Values Temperature Scale Set to Market Preference Outlet Temperatures Set to 22ºC Audible Warning Switched on

ATC ECU Manual Diagnosis Press & Hold Auto & Air Distribution Buttons Switch on Ignition Audible Warning Entire LCD Display Lights up Window Displays FC & Number

ATC Self Test Fault Codes

Fuel Burning Heater

Fuel Burning Heater 1.Combustion Air Fan 2.Electronic Board 3.Heat Exchanger 4.Stainless Steel Burner 5.Fuel Supply 6.Glowpin/flame Detector 7.Evaporator 8.Water Pump

Benefits of Fuel Burning Heater ·     Requires a Very Small Electrical Supply As Heat Is Generated by Burning Fuel and Therefore It Doesn’t Drain the Battery ·     Produces a High Power Heating Output of 5 KW ·     Good Thermal Efficiency ·    Environmentally Friendly Because of Optimum and Continuous Combustion