How Often Does Your Air Conditioner Need to Be Flushed?

The Right Time

• Tech experts from Air Condition.com suggest anytime the A/C unit is to be serviced, the internal hoses and components should be flushed out just to make sure the unit isn’t accumulating buildup. A more reliable schedule, provided you don’t regularly take your vehicle in to your mechanic’s shop for tune-ups, is every two to three years, depending largely on how much you use your vehicle and how often you run the vehicle’s A/C unit. If you live in a hot and humid environment, flush your units every two years, and if you live in more temperate or cooler environs, flush your units every three years. If your vehicle features an orifice tube, you can visually inspect the condition of the unit by checking out the screen; if it’s dirty, it’s time to flush the system.

Flushing the Unit

• Generally speaking, your vehicle’s A/C unit operates very much in the same manner as your refrigerator. The best and most comprehensive flush is to manually disassemble every working component to the A/C unit -- this includes all the attachment hoses as well. Flush each using the correct type of cleaning solvent, the type of solvent that doesn’t leave behind any type of residue that will otherwise contribute to buildup, leading you to have to flush the unit all over again. By flushing out the spent refrigerant and replacing it with new coolant, you’re eliminating all the contaminant that contributes to buildup.

What Not to Do

• While all the components should be flushed out every time you’re servicing the A/C unit, it’s best to leave the compressor, receiver, expansion valve and muffler assembly (if applicable) alone. These units are difficult to flush, are delicate and should be dealt with by a knowledgeable technician. In most cases, accumulated buildup warrants these parts to be replaced anyway.

A Word of Caution

• Checking refrigerant levels by poking an object into the fitting and checking for release is illegal in most jurisdictions, as this method errantly releases coolant gases into the air, a violation of many environmental protection laws. Similarly, once you’ve flushed the A/C system properly, only refill the system with the appropriate amount of coolant. Overfilling is unlawful and dangerous.