How do I test my car's evaporator?

Testing the AC evaporator in your vehicle requires special tools, such as an AC manifold gauge set or recovery/recharging machine and leak detection dye. The gauge set is connected to the AC service ports on the high and low side lines. A can of refrigerant with dye is charged into the system and the engine is allowed to run for fifteen minutes to recirculate the dye. Any dye present outside of the evaporator would indicate a leak. The problem is that you cannot simply observe the evaporator due to its location. And AC system service requires not only special training, but certification as well.

How long does a car evaporator last?

As with any AC system component, the lifespan of the evaporator will depend on driving conditions and environmental factors. A vehicle operated or stored near a humid saltwater coast will fall victim to corrosion in the AC system more readily than one located in a dry climate. And an AC system that is used frequently in extremely hot conditions will wear faster than one used occasionally in mild climes. On average, you can expect your evaporator to last 10-15 years or so.

What causes a car evaporator to go bad?

Excessive corrosion, a failed seal or o-ring, or physical damage to the evaporator core itself can all lead to a refrigerant leak. It should be noted that a refrigerant leak is not necessarily the same thing as a leak coming from the evaporator. The evaporator coils tend to collect condensation. For this reason, manufacturers include a water drain tube that leads from the HVAC housing where the evaporator is located to the underside of your vehicle. It is not uncommon to see a puddle of water underneath your vehicle when the AC is running.