Steps To Change The A/C Evaporator

Also known as the evaporator core, an A/C evaporator is one of the two or three heat exchangers that are commonly found in a car A/C system. In a typical pickup truck or passenger car, the evaporator is usually installed inside the passenger compartment, i.e. under the instrument panel. Some vehicles may have two evaporators. The second evaporator may be located at the front or rear of the vehicle. A/C evaporators are also made of aluminum and feature flow paths (internal tubes) that are like radiators. But the tubes are designed to carry moving engine coolant. Read on to find out what can go wrong with your evaporator and how you can replace it.


Understanding A/C Evaporator Issues

A common cause of evaporator problems is leakage. Leaks can occur for various reasons, including corrosion as well as a weld or seam that has gone bad. Apart from leak points, there are also things such as outside-in failures. These failures can occur because leaves and other organic materials may enter the evaporator case (through the exterior air intake vents). When these materials come in contact with the evaporator’s surface and start decomposing due to the moist atmosphere, they may form caustic corrosive substances. These substances will eventually perforate the surface of the evaporator.

Next, the same substances can also lead to an in-vehicle odor problem. The problem will be most noticeable when the A/C system is first operated. Fortunately, there is a variety of drying modules and deodorizing biocide treatments to resolve these issues.

No matter which type of evaporator failure you are facing, the unit must be replaced. In many cases, the evaporator in and of itself may not cost a bomb. The final cost also depends upon its location. However, changing an evaporator may entail a very time-consuming process.

How to Change the A/C Evaporator

Let’s begin the changing process with the removal phase:

  • Step one: Utilize a refrigerant recovery machine to safely recycle or recover the refrigerant (make sure the machine is designed for the specific refrigerant in the A/C system)
  • Step two: Remove the lines that are present in your thermal expansion valve
  • Step three: Detach hoses from the heater core
  • Step four: Remove the HVAC case
  • Step five: Open the HVAC case
  • Step six: Remove the evaporator core
  • Step seven: Wrap or cap the joint of the A/C compressor and piping (this prevents moisture and air from entering the A/C system)
  • Step eight: Remove old O-rings and replace them with new ones
  • Step nine: Apply lubrication on new O-rings
  • Step ten: Make sure oil levels in new condenser are balanced

Next, you are ready to install the new A/C evaporator. Here’s what you need to do:

  • Step one: Just reverse the steps that you have previously followed for the removal phase
  • Step two: Thoroughly vacuum the system
  • Step three: Recharge the refrigerant while adhering to manufacturer specifications
  • Step four: Check your A/C system to ensure that there are no refrigerant leakages

It is recommended that you have your vehicle’s A/C system professionally serviced. When you work with a mechanic, don’t be afraid to insist on quality replacement parts and proper repair procedures. If you are looking to get top-notch A/C parts for your car, do not hesitate to contact R & Y A/C Compressors today.