HEATING AND AIR CONDITIONING 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

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

ACR2000 Diagnosis

• A/C System Performance

• Pressure Zone Diagnostics

• ACR2000 Diagnostic Exercise

Retrofitting

• Legal & Cost Issues

• Equipment

• Retrofitting Process