Brew Boss with RIMS tube, high gravity beers - Beer, Wine, Mead, & Cider Brewing Discussion Community.

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Sep 13, 2011
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poplar grove
Just finished brewing a batch of Russian Imperial Stout with my modified Brew Boss system and couldn't be happier.

I've made 3 different size pots to use with the brew boss. 5, 15 and 20. I've run into trouble with high gravity beers due to biab's low efficiency. I'm not using the COFI system. I had a basket made for my pot and use the loc line fittings mentioned in other threads to recirculate the mash.

The problem comes in when doing a high gravity beer. The grain bill is so large and sits so high in the basket that a lot of extra water is required, especially when considering the 3 to 4 gallons of dead space under the basket. By using a rims tube and bag instead of the basket and heating element in the pot, I was able to use much less water to start the mash. I initially figured I would need about 11 gallons of mash water to cover my 23 lbs of grain. OG=1.092 That was figured using my basket. When I switched to the bag, I used 9 gallons and kept 2 for reserve in case I needed to sparge to hit my og. I put a stainless silverware basket around the exit elbow in the bottom of the pot to keep the bag from getting sucked in. I also kept the ripple heating element in place to use later for the boil. I also put a stainless basket around it to keep the weight of the grain off of it.

The rims tube is pretty standard. Pieced together the T portion with an short tube and an elbow, all tc fittings. I used a 5500W 240v straight tc heating element which paired perfectly with BB's system.

Plumbing was:

Mash tun exit to BB 12v pump, then valve, then into the T of the RIMS tube, then silicone hose to the lid and loc line arms inside the pot.

I did a 60 minute mash with no problems. I then drained most of the wort into another pot so I could batch sparge. I ended up with 75% efficiency.

I wasn't sure what the efficiency was going to be so I ended up having to boil for over 2 hours! Hope I didn't scorch!!

I boiled using the standard BB equipment.