10 in false bottom and dip tube question?

[eluterio]

Ive got an old Coors oversized Keg that I use for my MLT. I purchased a combo set from my LHBS that included a 10 in false bottom, 1/2 diptube, and valve. Ive used this FB for several all grain batches this year and have noticed my efficiency is about 65%. I usually fly sparge and drain out the wort as slow as possible. Ive tried a single infusion mash with same result. I havent tried a batch sparge just yet but I think that will be my next step.

With all this said I cant seem to figure out why im not pulling off a higher efficiency %. I need some input on how to correct this problem.

I also have question if it could be because of my FB only 10 inches in Diameter or if its because my diptube is sitting roughly 2 inches from the bottom or both?

I use a silicone o ring and place it on the bottom of the dip tube after I install the FB. When im emptying the grains the o ring is still attached, however, I do notice grains all around underneath the fb. I do rinse and usually takes about 1 gallon to show clarity. For precaution I also use a hop bag at the end of the hose to catch grains and it does but Ive never had a full hop sack.

I also have the option to switch dip tubes I purchased, after I learned from here, brew hardware's 5/8th dip tube. I have yet to measure the bend but thats my next step but this would require me drilling the 10 in fb to fit the 5/8th dip tube.

Lastly, i am getting a pump next week. Im nervous about the pump actually sucking down the fb off the dip tube since it sits high. Thoughts?

Thanks HBT!

 

[william_shakes_beer]

1. Where is the open end of the dip tube in relation to the bottom of the mash tun? Is should be at the bottom. (below the false bottom)
2. How are you drawing wort off the valve? The tube on the outside of the valve should extend below the bottom of the mash tun to develop a siphon and draw all the wort out of the mash tun.

 

[eluterio]

1. Where is the open end of the dip tube in relation to the bottom of the mash tun? Is should be at the bottom. (below the false bottom)
2. How are you drawing wort off the valve? The tube on the outside of the valve should extend below the bottom of the mash tun to develop a siphon and draw all the wort out of the mash tun.

1) The open end of the dip tube is approximately 2 inches from the bottom of the mash tun. It sits almost center of the keg and when the fb is in place it sits and covers the dip tube approximately 1/2in.

2) I have a standard 3 piece ball valve and use a 3/8in barb fitting and use a high temp 3/8in tube thats about 5 ft in length. I draw below the mash tun.

 

[chickypad]

If your dip tube is 2 inches off the bottom of the tun then it is not doing you any good. You are likely leaving high gravity wort behind. I have 2 inches of dead space below my false bottom, so I use a dip tube which goes right to the bottom of the tun.

 

[eluterio]

Any suggestion on how to modify this? would placing a piece of 1/2 high temp tubing work? I cant redrill the hole its at the base of the weld.

 

[Bobby_M]

Yes, a piece of tubing will work, just be sure to cut a couple v shaped notches in the bottom so it doesn't bottom out and create a seal.

 

[eluterio]

Yes, a piece of tubing will work, just be sure to cut a couple v shaped notches in the bottom so it doesn't bottom out and create a seal.

Thanks Bobby I suppose Ill try this my next batch. Any chance of this collapsing when using a pump?

 

[eluterio]

Is the reason for poor efficiency my dip tube isnt long enough?

 

[chickypad]

Is the reason for poor efficiency my dip tube isnt long enough?

Well that's pretty hard to say. I wouldn't consider 65% too poor - if it's reproducible you can always just throw in a couple extra lbs of grain. But you may be losing some pts if you're leaving a lot of wort at the bottom of the tun. For me 2 inches is 2 whole gallons. How's your crush?

 

[eluterio]

Well that's pretty hard to say. I wouldn't consider 65% too poor - if it's reproducible you can always just throw in a couple extra lbs of grain. But you may be losing some pts if you're leaving a lot of wort at the bottom of the tun. For me 2 inches is 2 whole gallons. How's your crush?

Actually, not sure how much dead space I have not sure if im losing 2 gallons or if its less than that. Ill be checking this out here soon as well. I crush my grains pretty well, I think. I use the LHBS mill and it crushes nice and a friend of mine has one that I need to run it through twice. From everything that I have read and seen I dont think my grains is the issue but it could be.