Bobcat 553 W0721 Error Code
W0721 Error Code
Hydraulic Oil Temperature OOR High is the main cause of W0721 error.The condenser converts gases into liquids, which expels heat from your rig. Materials can build up over time, causing a layer of dirt and grime to form on the condenser's coils. Your AC system will only blow hot air since the refrigerant fails to cool down.
Tip For 553 Model
It is recommended in cold weather to cycle the glow plugs twice before attempting to start the engine. This will allow for additional heating time for cold weather starting.