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