I am looking to buy a new Gas Furnace for my house. I have hot water heat. Someone I work with said a local store had a Carrier Gas Furnace FY4ANF042 for sale. I was just wondering if that was an actual Furnace or something else.

I have hot water heat.

You need a boiler not a furnace. That Carrier will not work because it is a indoor fan coil unit according to the number posted.