Hello HVAC pros: Where do you look on a Trane condensing unit to determine if it's a 3.5 ton, 4 ton, etc? This one's about 3 or 4 years old, not sure how to tell. Thanks! TK

1 ton = 12,000BTUs so typically, in the unit model number is the BTU rating. So if your model has a 48 in it, it will be a 4Ton unit(48,000 BTU). 3.5Ton = 42,000 BTU so look for a "42".