I have a 14 gallon stainless fermenter that was given to me. Off brand/ DIY job. It has a funky threaded-on nut system on the bottom with a 1" ball valve dump. It doesn't work well, to say the least. I am going to have a TC ferule welded onto the bottom, with the more common butterfly valve, sight glass, cap set up and a stout tanks racking arm with ferule installed on the side. My question is this: Is there any reason to NOT utilize a 3" dump valve on the bottom of the cone rather than the industry standard 1.5-2" other than cost? Seems the more of the bottom of the cone that is cut out, the better the trub/yeast dump function. Thanks in advance from the frozen NORTH!
I have a 24 gallon fermenter and I find 1.5" TC dump is plenty. Your logic makes sense but what might be gained in thorough tub removal may create a loss in extra beer. Fully open on my valve will create an unwelcomed rush. 3" might be harder to control. As you noted, price is also different for the valves but another point to add here is that if you like want to implement a clean-in-place setup you will need to pump from the dump and so you will also need to invest in reducer TC fittings and they are not cheap either.
Personally, I prefer to keep within the 1" - 1.5" diameters as they share fittings. Some items require larger fittings but when the option is available to stick with the standard size I go for it. It helps when reaching into a bucket of sani with a hose in your hand to know every clamp and gasket will work for your current needs.
Also, if you are going for these additions, I would throw out a couple ideas to think on. They may not be right for you but they work well for me.
It didn't take long for us to add an elbow to the dump line. Aside from making it easier to spray sani before opening, and easier for putting a cleaning line on, it holds a good amount of trub and yeast.
If the system can handle 2 psi, a TC ferrul on the lid can be used for a blowoff and later a hook up to a CO2 tank (TC to 1/4" threading to flare with 5/8" barb) for oxygen-less transfer to kegs. It also acts as your CIP
A port for a thermowell is worth the investment if you are having the work done. Dump, racking port (an arm is very handy), thermowell, and one or 2 ports on the lid would maximize your options. I don't know if you are paying for the work or not, but if it is cheap the ports only cost a few dollars each. That I would throw an extra few bucks at before a 3" valve.
