A/C recharges you shouldn’t buy in auto shops

Sherwood Cookie Jr., a leading technician at Royalty Automotive in Georgia, USA, warns drivers against buying DIY Freon cans from auto parts stores to recharge their vehicle’s AC systems, citing safety and environmental risks. There are at least two reasons why this can cause serious long-term problems.

Motor Biscuit wrote about them.

A/C recharges contain "stop leak"

An air conditioning recharger is a pressurized can that can be bought from an auto parts store and connected to a car's air conditioning system. It is said to raise the level of Freon in order to deliver cooler air.

Sherwood searched the shelves of the auto parts store and found only one can that did not contain Stop Leak. This additive is designed to temporarily seal holes.

It is believed that an air conditioning system with low CFC levels is bound to have a leak. The only problem is that it may leave the customer satisfied for one summer, after which the stop leak could seal the entire system.

Stop leak can also cause damage to the equipment used by car repair shops to work on customers' air conditioners. Such devices can cost $15,000 or more. Drivers may not be eager to repair service stations' equipment, either.

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Overcharging the system

An air conditioner requires a specific quantity of Freon to function correctly. Sherwood explains that, in order to achieve this, he flushes the system completely and then charges it with the exact amount of gas.

"Refrigerant machines have a scale in them. There’s an interior tank and it weighs that. It’s the only way you’re ever going to know that that system is full," the technician stressed.

The most expensive cans have a pressure gauge showing 'low', 'medium', and 'full'. However, Sherwood notes that this is just an estimate. The air pressure outside can severely affect its accuracy.

"People overcharge with these, and then the AC doesn’t work at all. You can overcharge, which could potentially cause damage. We see that a lot. If a $50 A/C recharge canister was a reliable way to fix your HVAC system, why would your technician bother buying a calibrated, $15k machine to do the same job?" Sherwood summarized.

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