Do You Know How To Spot And Fix A Leaking Auto A/C Evaporator?

The evaporator is designed to exchange heat, and although visually it looks like a condenser, it is smaller. Most use a fin and tube design, and in the majority of modern automobiles, it will typically be found within the passenger cabin, just beneath the instrument panel. In larger vehicles, such as SUVs and vans, it isn’t unusual for two evaporators to be present. Below are some reasons why these devices sometimes leak, and how to identify and fix a leaking auto A/C evaporator.

Why Are Evaporators So Important?

The evaporator is tasked with managing the pressure of the refrigerant. This pressure will decrease from high to low which leads to the refrigerant boiling and evaporating. The heat absorption which occurs due to this change causes the evaporator to become cold, which then allows it to capture excess heat from external air or to recirculate the air prior to it getting inside the passenger cabin.

Despite their similarities, it should be noted that the evaporator is distinct from a heater core. The heater core is responsible for transferring heat between the engine and cabin, while the evaporator does the reverse, moving hot air outside the vehicle, then subsequently cooling it and moving it back in. Both these components need multiple cooling and heating parts to function correctly.

What Causes Evaporator Leakage?

When leakage occurs within an evaporator, it usually means that either a weld or seam has become faulty. This could be the result of street debris which can enter the evaporator fins and then clog them. Leaves are notorious for doing this and the best way to fix it is by removing and replacing your evaporator.

Another cause is corrosion. Debris, organic materials and leaves can gain entry inside the case for the evaporator through the vents of the external air intake. Once they do, they will attach to the surface of the evaporator, and the moisture and decay which occurs within these materials can lead to the development of substances which are corrosive and which will ultimately damage an evaporator.

How to Fix Evaporator Leaks

Before performing repairs, the air conditioner will need to be correctly evacuated to ensure there are no gauges or pressure readings which are positive. The exact steps involved with removing and replacing an evaporator will vary from one vehicle to another, but in many automobiles the whole dashboard has to be removed in order to get to it. If the vehicle has two evaporators, the second will often be found in the vehicle’s rear, usually behind the side panel or inside the ceiling above the back seats.

Additionally, the cost of evaporator replacement will also vary between models. Due to the complexity that is involved with A/C systems, unless you have the skills it is best to hire a licensed technician.