How many pounds of freon do you need for your air conditioner? If you don’t buy a pre-charged line, or are looking to recharge your AC, you have to have a rough idea of how much freon you will need. Further on, you will find a chart showing how many pounds of freon you need for 2, 2.5, 3, 3.5, 4, 4.5, 5, and 6-ton AC units.
Quick Example: A 3-ton Carrier Infinity series AC unit is charged with 9.26 lb of R410A refrigerant. A bigger 4-ton AC is charged with 12.94 lb of R410A freon, according to the Carrier Infinity specifications sheet.
Now, we have to be aware that the amount of refrigerant needed depends on several factors, including:
- AC Size (Tonnage). This is the primary factor. The bigger the AC, the more freon you will need. That’s why the refrigerant weight chart further on is based on AC tonnage.
- Length Of Line Set. We have different standard line lengths, from 16 ft to 35 ft and up to 100 ft. The longer the line set, the more refrigerant you will have to use. Example: 5 lb of R22 might be enough to charge a 16 ft 2-ton AC line set. For a 50 ft 2 AC line set, you might need up to 10 lb of R22 freon.
- Type of refrigerant. How much freon you need depends on the type of freon as well. Freon types include R22, R410A, R32, and so on.
In practice, we usually focus just on 1 factor; the AC tonnage. In HVAC, we use a rule of thumb that says:
“You need 2 to 4 pounds of freon per ton.”
For HVAC technicians, this means that they have to pack 20 lb in your van if you go out to charge a 5-ton AC unit. If you are on a call for a 2.5-ton AC unit, you would pack a 10 lb unit. This is because we always calculate that we need a maximum of 4 pounds of freon per ton of cooling.
Based on this, we can quickly make a rough estimate about the weight of freon we need for the job. Here is this chart:
Freon Weight Chart For 2-6 Ton AC Units
| AC Tonnage: | Pounds Of Freon (lbs): |
| 2 Ton AC | 4 To 8 Pounds |
| 2.5 Ton AC | 5 To 10 Pounds |
| 3 Ton AC | 6 To 12 Pounds |
| 3.5 Ton AC | 7 To 14 Pounds |
| 4 Ton AC | 8 To 16 Pounds |
| 4.5 Ton AC | 9 To 18 Pounds |
| 5 Ton AC | 10 To 20 Pounds |
| 6 Ton AC | 12 To 24 Pounds |
As we can see from this chart, you would need anywhere from:
- 4 lb to 8 lb of freon for a 2-ton AC unit.
- 5 lb to 10 lb of freon for a 2.5-ton AC unit.
- 6 lb to 12 lb of freon for a 3-ton AC unit.
- 7 lb to 14 lb of freon for a 3.5-ton AC unit.
- 8 lb to 16 lb of freon for a 4-ton AC unit.
- 9 lb to 18 lb of freon for a 4.5-ton AC unit.
- 10 lb to 20 lb of freon for a 5-ton AC unit.
- 12 lb to 24 lb of freon for a 6-ton AC unit.
These are rough estimates for all refrigerant types (like R22, R410A, R32, and so on).
From the Carrier example above, we can see that these ranges are quite good for estimates:
- 3-ton unit requires 9.26 lb of R410A. The range for 3-ton units is from 6 to 12 lb. These 9.26 lb are right in the middle of this estimate.
- 4-ton unit requires 12.94 lb of R410A. Again, this is very close to the middle of the 4-ton range (from 8 to 16 lb).
Hopefully, you now know how to estimate how many pounds of freon you need for any size AC unit. If you need a bit of help figuring this out, you can use the comment section below, tell us about your AC, and we will help you out.