Yep whatever works.. ! :mrgreen:
If you're doing a large batch like 20-23l then getting a full biab will need a 40l + pot, and Pecos and the Ace boilers are too small for that. So a separate sparge vessel to sparge is needed.
If I make a 10l batch in my 15l pot I have to sparge seperately, either dunk or pouring water over the grains.
I've worked out a new trick to get big beers of 23 litres out of my Ace boiler and I reckon you could do the same with any other boiler of similar size. Ditch the bag. No more dragging steaming hot heavy bags out of the boiler to let them drain. Just loose grain in teh boiler, strained through the filter on the tap. Deal with the grain after the sparging.
This is what I did.
1. heat up 15 litres of strike water to the required strike temp in the boiler.
2. stir in the grain (in my case 6.150kg). When fully mixed, button it all up and slip a sleeping bag over the boiler for sixty minutes.
3. Place a clean FV under the tap and drain out the wort. If you started with the volumes I listed above you'll get about 9 litres out of first run wort. Grain retains about 1 litre of water per kg used in the mash - hence the apparent loss.Sparging is done to get at this strong retained wort.
4. Tip in 10 litres of sparge water at 75C. Stir so that the whole grain mass is fluid in the wort. and leave for twenty minutes, stirring now and then to make sure you get maximum rinse of sugars from the grain.
5. Drain again into the FV. This time you'll get ten litres out because the grain was already soaked so no more is retained.
6. Tip in another 8 litres of sparge water at 75C, stir as before and leave for ten minutes with the occasional stir.
7. Drain all wort from the boiler, tipping forward at the end to get what is left in teh dead space below the tap.
Now you have to clean the boiler. Sounds bad, but it isn't. I brew up the top of the garden in a shed and have a hose pipe up there for water supply AND a compost bin in the corner of the garden. Put about ten litres of hose pipe water into the boiler, pick up the lot and swill it about a bit to fluidise the spent wort and water and upend it into the compost bin. Any straining type vessel would work for this if you don't have a compost bin and want to put the spent grain in the ordinary waste bin later.
My boiler took two good swills to get 99% of the grain out and a last one to leave it entirely clean. It wasn't too heavy to handle - maybe 18 or 20 KG all up. If you can't handle that much, this method probably isn't for you, but I'm 65 and found it easy.
This method will leave you with more wort than you can fit in the ACE boiler (25l max) so I retain the small balance of a few litres and boil that on the indoor kitchen stove while the ACE is steaming off in the shed for its boil. As it boils down I bring the boiled spare wort from the kitchen and top up the boiler. I ended with 23 - 24 litres of finished wort.
I got really clean wort out of this. The strainer in the boiler left the wort far cleaner than the mesh in my BIAB bag did - much finer than the bottom mesh of the bag, so much less trub after the boil. I also managed a high efficiency (about 75%) getting 1066 out of 6.150 kg of grain and about 23l of wort.