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 Gilmore's Auto Service, 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
Elizabeth Stokes, 12/08/2025After moving to Walnut Creek I was in need of an auto service repair shop; through a referral I started taking my car to Gilmore’s. Over the last year or so I have needed to take my car in for a one or two issues as well as basic oil change & have been very happy with service. They are very thorough in their work & have been really good on keeping me updated on repairs or service in general. They also are good about following up and checking in after service has been completed to make sure everything is in working order. Everyone I have interacted with is very friendly and accommodating. Josh especially is really great. Although their service fees are a bit higher than those I paid at my previous shop, I feel like I’m getting my money’s worth. If you’re looking for a good Auto repair shop, I definitely recommend Gilmore’s!
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