The drier is a component of the AC system that filters out moisture and contaminants. Look for a cylindrical canister with several fittings. The low-pressure port is usually smaller than the high-pressure port and will often be marked with a smaller diameter fitting or a label indicating "low" or marked with a blue cap. It's often located near the compressor or along the lines running under the hood.
To find it more precisely:
1. Consult a repair manual: A Ford Econoline repair manual specific to your van's year and model will provide a diagram showing the AC system components and the location of the ports. This is the best approach.
2. Look near the compressor: The compressor is a large, often ribbed component typically located near the front of the engine. The low-pressure lines connect to the drier, and that's where you're most likely to find the low-pressure port.
3. Follow the lines: Trace the thinner AC lines (the low-pressure lines are usually smaller in diameter than the high-pressure lines) to see where they connect.
4. Look for colored caps: The low-pressure port often has a blue cap, while the high-pressure port typically has a red cap.
Safety First: Remember that the AC system contains refrigerant under pressure. Do not attempt to work on it unless you are properly trained and equipped. Improper handling of refrigerants can be dangerous. If you're unsure, take your van to a qualified mechanic.
