Automatic Temperature Control

• Description
• Components & Functions
  • Programmer
    • Notes
    • Vacuum Motor
    • Vacuum Checking Relay Valve
    • Vacuum Valve
    • Transducer
    • Amplifier
    • Feedback Potentiometer
    • Resistor Assembly
    • Blower Switch
  • Control Head
    • Thumbwheel
    • Selector Lever
  • Sensors
    • In-Car
    • Ambient
  • Aspirator
  • Ambient Switch
  • A/C Override Switch
  • Engine Thermal Switch
  • Auto Relay
  • Lo Relay
  • Mode Door Diaphragms
  • Outside Air Diaphragm
  • Defroster Door
  • RESTRICTORS
• Operation
  • Notes
  • "Off"
  • "Economy"
  • "Lo"
  • "Auto"
  • "Hi"
  • "Bi-Level"
  • "Def"
• Functional Test
  • Notes
  • "OFF" - Dial @ 65
  • "ECONOMY" - Dial @ 65
  • "LO" - Dial @ 65
  • "AUTO" - Dial @ 65
  • Rotate Dial To 85
  • "HI" - Dial @ 65
  • "BI-LEVEL" - Dial @ 65
  • "DEF" - Dial @ 65
• Theory Of Operation, Testing & Adjusting
  • Theory Of Operation
    • Notes
    • Changing An Electronic Signal to Electrical Voltage
    • Changing The Voltage To A Vacuum Signal
    • Changing The Vacuum Signal To Mechanical Energy
  • Testing
  • Adjustments
    • Amplifier Calibration (Programmer Removed)
    • Temperature Door Link
    • Temperature Dial Calibration
• Trouble Shooting
  • Blower Inoperative
  • Blower, Programmer & Compressor Inoperative
  • High Blower Only; "HI", "AUTO", or "DEF" Give Max Heat
  • Low Blower Only With Max Heat
  • Low Blower Only With Selector At "A/C" or "HEAT"
  • No Low Blower in "OFF", "ECONOMY" & "LO" Positions
  • Immediate Blower (Cold Engine), In-Car Temp Below 70°F
  • High Blower, "DEF" Only; In-Car Tamp Below 70°F
  • Compressor Inoperative Above 40°F Ambient Temp
  • Compressor Operates Below 25°F
  • Max Heat Mode in "LO", "AUTO" or "HI", No Temp Control; No Automatic Blower Changes
  • In "AUTO" Range, No Temp Control, No Automatic Blower Changes
  • In "AUTO" Heat Mode (All Positions), No Temp Control, No Automatic Blower Changes
  • In Max "HEAT" Mode, Cold Air From Heater Outlet
  • Max A/C In All Positions
  • Max Heat In All Positions
  • Max A/C Only In "AUTO" Range; Cold Air From Outlets
  • Erratic Temperature Control
  • Temp of Discharge Air Too Hot or Too Cool At Mode Change
  • Insufficient Heat
  • No Mode Change In "AUTO" Range From A/C To Heat
  • Excessive Temp Difference At Outlets In "BI-LEVEL" Operation
  • Partial Air Flow To Windshield in "DEF"; No Air Flew To Windshield in "BI-LEVEL"
  • No Air Flow To Windshield In Either "BI-LEVEL" Or "DEF"