What's the difference between a "top-off" and an "evacuation and recharge"? Why
Date: Wednesday, August 21 @ 17:25:02 CDT
Topic: News from A/C Authority
A top-off involves simply charging refrigerant into your vehicle. An evacuation and recharge service includes removing whatever remaining refrigerant is in your vehicle, removing impurities from that refrigerant using recycling equipment, recharging it into the vehicle, and adding new refrigerant to replace whatever has leaked out. The cost of both the top-off and the evacuation and recharge will usually include a performance check, and may include a test to discover the source of your leak.
Topping-off alone is less expensive than the evacuation and recharge service. So why would you consider the more expensive evacuation and recharge? The manufacturer of your vehicle has determined that a specific amount of refrigerant -- 2.2 pounds, for example -- is correct for your car. When you bring your vehicle into a service facility, your technician has no way of determining precisely how much refrigerant is left in your vehicle's system. As he tops off the system, then, he relies on his experience to guess how much refrigerant to charge into the system; however, he may undercharge or overcharge the system, thereby affecting system performance. Most recent models have a feature that shuts an overcharged a/c system down in hot weather.
On the other hand, during an evacuation and recharge, once the technician has extracted all remaining refrigerant from the system, he will then be able to charge the system with the precise amount of refrigerant recommended by the vehicle's manufacturer.
Some technicians may tell you that evacuation and recharge is better for the system than a mere top-off because, after the refrigerant is evacuated, it gets cleaned in the recycling equipment, and it's a good idea to clean the refrigerant in your system. There is, in fact, no reason to clean the refrigerant in your system unless you open up the system. If you request that your technician repair or replace system components in order to fix leaks in your system, then he will need to open the system and should recycle the refrigerant.