HVAC SYSTEM DIAGNOSIS

Manual HVAC Control Systems
• Vent
• Preventing evaporator freeze-up
• Light duty trucks
• Rotary vacuum valve
• Two wire motor
• It causes a skewed signal in the
• feedback circuits
• Absence of source vacuum
• Verify
• Preliminary checks
• Perform system diagnostic checks
• Check for bulletins
• Diagnosis
• Isolate the root cause
• Repair and verify fix
Special Configurations
• Dual Zone HVAC Control Systems
• Rear HVAC Control Systems
• HVAC Steering Wheel Controls
• Customer Concerns
• Diagnostic Exercise
• ACR2000 Diagnosis
• A/C System Performance
• Pressure Zone Diagnostics
• ACR2000 Diagnostic Exercise
• Retrofitting
• Legal & Cost Issues
• Equipment
• Retrofitting Process
Automatic HVAC Control Systems
• Inside air temperature from 65-85
• degrees regardless of outside
• temperature
• HVAC controller
• The HVAC controller will try to
• maintain set temperature as much as
• possible
• Monitor the discharge temperatures
• from the heater and A/C outlets
• All sensors have reached the same
• ambient temperature