The most important brew kettle consideration for homebrewers is capacity: the kettle needs to be at least a few gallons larger than the volume of wort to be boiled. A partial boil extract batch (2-3 gallons of wort in the kettle) can fit in a 5 gallon brew kettle. For a 5-gallon full boil extract, partial mash or all-grain brew (6-7 gallons of wort in the kettle), you’ll need an 8 to 10 gallon brew kettle. Homebrewers who want to make a 10-gallon batch with a full volume boil will need a 15-gallon brew kettle.
Kettles also come in different lines with different features.
At the most basic level, there are 5 gallon and 7.5 gallon economy brew kettles. They are great entry level kettles and last many brewers their entire homebrewing careers. They have a light, easily cleaned stainless steel construction. The bottoms may have ridges, making them primarily compatible with gas stovetops.
At our intermediate level are the Megapot kettles. They have a higher grade of stainless steel, and have a stainless steel clad aluminum bottom. The aluminum provides better heat transfer and distribution, while there is only stainless steel touching your beer, as well as the burner. They are induction cooker ready, and they are available with optional ball valves, which allows you to drain liquid without lifting the pot, and brewing specific thermometer, which allows you to easily read temperatures without removing the lid. Megapots are suitable for use as a boil kettle or, with a false bottom, as a mash tun for all-grain brewing.
The finest line of kettles that we have is the Blichmann Boilermaker line. These are the only kettles that have been designed from the ground up for homebrewing. They have a high polish finish for easier cleaning and are made of high grade stainless. They come standard with a rebuild-able 3-piece stainless ball valve with a dip tube, an adjustable angle brewing specific thermometer and an easily cleaned graduated sight glass for measuring the volume of liquid. Their stepped bottom mates nicely with their hybrid false bottom/manifold and the dip tube fits well with the Hop Blocker, another Blichmann product.