How Much Refrigerant Is In an Air Conditioner?

Check the Nameplate

• Since there is no single answer to the question of how much refrigerant is in an air conditioner, the best option for finding out is to learn all you can about your own system. Look at the manufacturer’s label mounted on the unit. This nameplate often has the manufacturer's name on it, as well as some other valuable information. You’ll find the model number on the unit, which you can use to call the manufacturer and ask how much refrigerant is required for it. Furthermore, the nameplate often includes the type of refrigerant required and how much is needed for typical use. While the nameplate may not always have all the information, it is a good place to start if you are wondering.

Pressure and Pounds

• One detail to know about air conditioning refrigerant is that the amount of refrigerant heavily depends on the size of the system. How many tons of cooling capacity the system has will help determine how much refrigerant it needs to do the job. The bigger the unit, the more refrigerant it requires. The amount that gets put into the air conditioner is measured in pounds and ounces, but when an HVAC technician comes to your home to check refrigerant levels in your air conditioner, he reads it in pressure, not physical amounts. Larger air conditioners require more refrigerant to get the gauges to read a higher pressure. Meanwhile, a smaller air conditioner can achieve the same pressure with much less refrigerant.

Long Line Sets

• A factor that heavily influences the amount of refrigerant needed in your air conditioning system is the line set. These are the copper refrigerant lines that run from the outside evaporator to the inside unit on a central air system. Most 15-foot line sets require the amount of refrigerant indicated on the nameplate, if applicable. However, if you have an extra long line set attached to your system, then you can expect to add up to two more pounds of refrigerant to get the proper pressure readings.

Why It’s Important

• If you wonder what difference it makes if there is too much or too little refrigerant in the system, it makes a lot of difference. When an air conditioner is low on refrigerant, it may not cool properly. It can also lead to icing on the evaporator coil that will damage the system. If you have too much refrigerant in the air conditioner, it can damage the expensive compressor. Overcharging with refrigerant may also encourage leaks in the lines.