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9.0 DIAGNOSTICS & TROUBLESHOOTING
9.6 Cooling Mechanical Checks Flowchart
Diagnostics
Indoor Metering Device
Stuck Open - Low
or No Suction Superheat
High Head Pressure or
Compressor Envelope
Protection
YES
NO
Pressure
Problems?
Low Liquid
Pressure
Low Suction
Pressure
Go to Electrical
Checks Flowchart
Dirty Filters
Dirty Indoor Coil
Inadequate Indoor
Airflow
Inoperative Indoor
Blower
Low on
Charge
Low Ambient
Temperature
Bad
Compressor
Dirty Outdoor
Coil
Inoperative Outdoor
Fan
Overcharge
Recirculation of
Outdoor Air
Noncondensibles
Restricted
Filter Drier
Higher Than Ambient Air
Entering Outdoor Coil
Wrong Outdoor
Fan Rotation
Inadequate Ducts
Restricted
Filter Drier
Outdoor Unit
Running?
Low on Charge
Restricted Indoor
Metering Device
Restriction in
System
Recirculation of
Indoor Air
Wrong Indoor
Blower Rotation