HLT sizing...

So, I'm in the midst of putting together my 20 gallon capacity AG setup. I already have (1) 100 quart pot (25 gallon), and my 24.2 gallon conical tank from Toledo Metal Spinning (pulling a Yuri DIY special).

My question is this... Can I get away with using a 15.5 gallon keg for my hot liquor tank? Both my mash tun and boil pots will be 100 quart, but if I can avoid purchasig a third $200 pot... I'd be happy. At no point I will need to hold the full 20 gallons, so I figure it should be large enough, right?

My system is going to be a true HERMS... I plan on running a copper heat exchanger coil within this HLT. Eventually it will be totally automated, but that extra $200 can be used for other stuff at this time, and I'm going to pick up about 6 or 7 kegs tomorrow for FREE.

Thanks

I do 10 gallon batches, and my 15 gallon is more than enough. . . I use it for HERMS and use it for my sparge water as well. I'd think that a 15 gallon keg should be fine for a 20 gallon setup.

I'm currently at the bare minimum for a 15 gallon setup - a 60 quart cooler/mash tun, 20 gallon boil kettle, and 9 gallon HLT. With a ~30 lb grain bill, I've been winding up with just under 15 gallons of finished beer. The small HLT is my limiting factor right now, but I don't really want to spend the bucks for another big kettle at the moment (that'll probably be my next upgrade, though). I think your 15 gallon HLT will probably suit just fine for 20 gallon batches.

Perfect... Thanks for the input fella's.