2016 Freightliner M2 106 - Orifice Tube

What is an A/C Orifice Tube?

The A/C orifice tube functions as an expansion device for the A/C systems, allowing refrigerant to transition from a warm high-pressure liquid into a cold low-pressure liquid before it reaches the evaporator. All A/C systems will have either an orifice tube or an expansion valve to perform this task, and orifice tube systems will also feature an accumulator that collects refrigerant before it is recycled by the compressor. The orifice tube has no moving parts, but may still clog or wear out over time and cause A/C system issues. If the air from your vents is not getting cold or is becoming too cold, you may need a replacement orifice tube. Restricted refrigerant flow may also lead to intermittent cooling, or the A/C compressor not activating. If too much refrigerant is flowing through the orifice tube, it may cause the A/C compressor to run continuously, the evaporator to freeze, or produce frost on your cabin vents. It is also typically recommended that the orifice tube be replaced any time the A/C system is opened for service to ensure lasting performance. At O'Reilly Auto Parts, we carry orifice tube replacements, accumulators, condensers, and other A/C system parts for a complete air conditioning repair.