How to Add Refrigerant to an AC Unit Yourself

If your house won't cool down and you're looking up how to add refrigerant to an AC unit, here's the problem: it isn't a DIY job. Federal rules limit refrigerant sales to certified technicians. More importantly, an AC that's low on refrigerant almost always has a leak, and adding more won't fix it.

Can I Add Refrigerant to My AC Myself?

No, you can't legally add refrigerant to a home AC system yourself. Under the EPA's refrigerant sales restriction, only certified technicians can buy it. The small cans you can pick up without certification are for car air conditioners, not the system outside your home.

Handling it is risky, too. Refrigerant is stored under high pressure and can cause frostbite if it touches your skin. Technicians also charge each system to the exact amount the manufacturer specifies, since too much refrigerant can damage the compressor and too little leaves you with weak cooling and higher bills.

Does AC Refrigerant Run Out on Its Own?

No, AC refrigerant doesn't run out on its own. It circulates through a sealed loop, carrying heat from inside your home to the outdoor unit. Unlike gas in a car, it doesn't get burned up as the system runs.

So how often does AC need refrigerant? After installation, it shouldn't need any. A system low on refrigerant was either undercharged at installation or has a leak.

That means it isn't normal for your AC to need refrigerant added every year. If your AC refrigerant keeps running out, a yearly top-off only pays for refrigerant that will escape again. A technician needs to find and repair the leak first. Unfortunately, leaks can keep going even when your system isn't running.

How to Tell If Your AC Needs Refrigerant

Warm air from the vents and frozen coils are two of the most common signs your AC is low on refrigerant. Other warning signs of a leak include:

• The system runs longer than usual without reaching your thermostat setting

• Your home feels unusually humid

• You hear hissing or bubbling near the unit

• Your electric bill climbs for no clear reason

Before you call, check your air filter. A clogged filter can cause some of the same symptoms, including frozen coils.

If your AC is low on refrigerant, it works harder to move the same amount of heat, so comfort drops while energy use goes up. Over time, that strain can overheat the compressor, one of the most expensive parts to replace.

How to Check AC Refrigerant Level

As for how to check your AC refrigerant level, leave that to a technician. They'll use gauges to measure refrigerant line temperatures and compare the readings to the manufacturer's specs. Fall AC maintenance gives a technician the chance to catch a slow leak before it becomes a bigger AC repair.

The EPA-certified technicians at Satterlee Plumbing, Heating and Air Conditioning find and fix refrigerant leaks for homes and businesses in Joplin, Carthage, Webb City, and Neosho, Missouri; Pittsburg, Kansas; Bentonville, Arkansas; and Grove and Miami, Oklahoma. Schedule your free estimate today.