2 ton
That isn't a typical Rheem model number, are you sure that isn't the serial? If it is the model number it is a 2.5 ton :)
How many tons RAHE-042JAS
2.5 tons
5 Tons
2
2.5
five ton
5 ton
3 ton
5 tons, denoted by the 60 in the model #, (5x12=60).
3-ton