Replace Your Car's AC Thermal Expansion Valve or Orifice Tube
Your car or truck's AC system is under extreme pressure and the thermal expansion valve or orifice tube monitors the amount of pressure and the temperature of your A/C system. It calculates the precise amount of refrigerant that can safely go into the evaporator. A failing expansion valve or orifice tube often causes a vehicle's air conditioner to blow hot air.
Replace or Repair
- Expansion Valves: Too much refrigerant causes your evaporator to get too cold whereas too little refrigerant would result in inadequate cooling. The expansion valve is a complex valve that regulates refrigerant flow. This process of metering the refrigerant adjusts the flow according to the temperature of the refrigerant in the evaporator coil. Talk to one of the pro mechanics at Muffler and Go Full Auto & Transmission, as this part can be replaced on its own and does not require the entire replacement of the AC assembly.
- Orifice Tubes: Unlike the expansion valve, the orifice tube is a simple fixed device with no moving parts. It therefore cannot vary the flow of refrigerant into the evaporator, but rather causes a permanent restriction in the system. However, like the expansion valve the orifice tube regulates refrigerant flow through the system and filters debris which may come through in its screen. Often fixing a "bad orifice tube" requires replacing the entire evaporator assembly.
OUR REVIEWS
Fenton, MI
Brian Kelly, 09/24/2026Muffler & Go serviced my 2002 Jeep Wrangler, and I had a great experience. Owner Chris and his team thoroughly inspected my Jeep and clearly explained which repairs should be addressed now and which could reasonably wait until a later date. Their honesty and professionalism were greatly appreciated. The team did an excellent job, and I was very satisfied with the service. My only suggestion for improvement would be to have a dedicated front desk person to help with customer check-in and communication during busy times. Overall, I would highly recommend Muffler & Go for their quality work and customer service.




