My air conditioner has how many BTU's ?

There should be a plate or sticker on it that tells you what the air conditioner's rating is, in BTUs.

We have no idea. Most are rated in BTU, some in tonnage. 12,000 BTU = 1 ton. If this is a central unit, it will typically have some numbers as a code. E.G. 24 or 36 or, in my case, 48 which is 4 ton. Window units are usually BTU. What do you have?