Horrible flow on new false bottom

I recently bought/installed a false bottom for my 5 gallon round mash tun after using a simple hose braid for years. However, first use during Big Brew Day on Sat was disastrous. After mashing for 60 mins, turned the spigot of the tun gently to start the vorlauf and......nothing. No one drip. Screwed around with it, stirred, finagled, etc. Got the initial runoff drained, but when I batch sparged....nothing.

So, we thought outside the box, got a huge grain bag from inside the LHBS where the event was held & dumped the mash into the bag in the kettle. Voila! A biab! Worked fine the rest of the way, but in hindsight am trying to figure out the issue with the false bottom.

After cleaned out & disassembled, I realized the problem was probable that the plastic elbow was screwed too far down which pressed it too close to the bottom of the cooler, completely blocking drainage. Ok, so I adjusted & tried again with just a gallon or so of water.....

It flowed ok, but veeeeeery slooooowly. Just drizzling out of the spigot. It would take about 18 hours to collect 7 gallons. WHat's the story here? Did my LHBS just sell me a ****ty false bottom? Why is the flow so bad? I'll return the thing & go back to a cheap hose braid if this is what I'm looking at. Totally disappointed - was siked to upgrade, but just worked horribly.

Looking at the elbow, am curious if its just too small to allow quick fluid movement. The hose braid would allow full flow, almost too quick, unless I regulated. In the test, I had the valve all the way open & was just ridiculously slow.

Any ideas here? Return to hose braid?

If this is a plastic false bottom then it may have collapsed under the weight of the grain. I've heard of others who thus has happened to. This is why most guys these days are using the stainless false bottoms. It ca take a lot of weight and you don't have to worry about it collapsing. I only say this because you mention the plastic elbow. if the weight is too much the spigot off the elbow will be smashed down to the bottom of the cooler and o course you won't get anything out.

A couple things that work for me....I always have mash water in the cooler so the grains don't compact too quickly.
Also, with a long spoon press down on the false bottom while you dump your grains in,,,,,while inspecting my bottom I noticed it had the tendency to lift slightly which could potentially let grain in under the sides if I don't press down on it.
Another thing, tapping the false bottom sometimes starts the flow.....oddly enough I've turned the spigot and nothing but tapping it will all of a sudden start the flow, I don't have any idea why this works.
Last resort, blowing in while pushing down on the bottom will some times start flow,,,blow as little as possible and be sure to press down otherwise the air you blow in will lift the false bottom off the cooler bottom (arrange the top so it's on slightly leaving an area to slip spoon in, otherwise don't Be surprised when on water lands on your back).
A few other things, make sure the pieces are well screwd together and be careful when stirring, I've stirred and actually unscrewed the L from the rest of the bottom, I've also wondered if my stirring didn't partially lift up the bottom from the movement of m spoon rising to quickly up creating suction and pulling the false bottom up...
Good luck!

Sometimes I get an air bubble in the valve or the hose from the false bottom to the valve and just get a dribble coming out. I pick up the end of my tubing that goes from the MLT to the kettle so that it is just higher than the ball valve and let the remainder of the tubing (lower than the valve) fill with wort, then lift the end of the tubing way up so the wort will drain from the tubing back into the MLT. Then put the end of the tubing back in the kettle and it should start flowing.

DeafSmith said:

Sometimes I get an air bubble in the valve or the hose from the false bottom to the valve and just get a dribble coming out. I pick up the end of my tubing that goes from the MLT to the kettle so that it is just higher than the ball valve and let the remainder of the tubing (lower than the valve) fill with wort, then lift the end of the tubing way up so the wort will drain from the tubing back into the MLT. Then put the end of the tubing back in the kettle and it should start flowing.

Click to expand...

^this is what I think tapping the bottom does, knocks the air out the line.

Sorry, I forgot to add what it is a stainless steel false bottom. Also, as I was testing with just water would the above apply? There was nothing in the MLT other than about 2 gallons of water. Nothing else. Shouldn't that flow as quickly as the valve is open? Since I had the valve all the way open, I thought it would come full throttle. Nope....just a tiny drizze & no grains, etc. to restrict the flow....

Can you post a pic of your setup? How much clearance is there betwen teh pick up tube and cooler bottom? Could the false bottom be pushing it down more under weight, forming a seal between the cooler bottom and pick up tube? Maybe trim an 1/8" off the pickup tube and try.

Well, initially I think I had the elbow pick up screwed too far down which was pressing against the bottom of the cooler & preventing ANY flow. There was zero movement. Then, in my water test, I dialed the elbow back so it was just barely screwed in & should have plenty of clearance & there was just a trickle.

I've attached a pic of the setup. One clamp is just sitting loose as I've been fiddling with it.

My guess is air pocket.

jmd1971 said:

Sorry, I forgot to add what it is a stainless steel false bottom. Also, as I was testing with just water would the above apply? There was nothing in the MLT other than about 2 gallons of water. Nothing else. Shouldn't that flow as quickly as the valve is open? Since I had the valve all the way open, I thought it would come full throttle. Nope....just a tiny drizze & no grains, etc. to restrict the flow....

Click to expand...

i've had the same problem testing with just water - I had to backflush to get the air out before it would start flowing.

jmd1971 said:

Well, initially I think I had the elbow pick up screwed too far down which was pressing against the bottom of the cooler & preventing ANY flow. There was zero movement. Then, in my water test, I dialed the elbow back so it was just barely screwed in & should have plenty of clearance & there was just a trickle.

I've attached a pic of the setup. One clamp is just sitting loose as I've been fiddling with it.

Click to expand...

Is this a 10 Gal cooler? You might want to try testing it with more than 2 gal of water. Might not be enough force of gravity to start the flow. I have a very similar set-up to yours (mine is a metal elbow) and don't usually have any problems with drainage. I did in my last batch, but that's because the spigot was clogged with some rogue grains.

Try drilling a couple holes in the threads of your plastic elbow below the FB. That's what I had to do to solve this problem.
Even with only water, the vacuum can sometimes be enough to pull that elbow onto the bottom and block your flow. With grain weight on top of it, it's almost guaranteed.
Technically your LHBS should be selling those elbows with the holes in them already. I know mine does.

Secondly, when I put in my water in to pre-heat my MLT, I tap the false bottom with my mash paddle and circulate a little bit of water through the valve to make sure that there is no air in there.

Your problem most likely is that the tubing you are using, while it is made for high temp, is being crushed by the weight of the grain bed.

I have that type of hi-temp silicone tubing and it should only be used outside of the tun or any other vessel.

What you want is the opaque and more rigid silicone tubing.

Follow this link to see what I am talking about....

http://www.williamsbrewing.com/38-HEAVY-WALL-THERMOPLASTIC-TUBING-50-roll-P3039.aspx

Change your tubing and you should get great results, like I did today.

We're you by chance at the Home-brew Emporium in Weymouth ma? Stopped in today and while I was picking up my grain the guy was telling me about this guy who had a stuck mash during the free ingredient event.

Also, increasing the length of transfer hose outside your mash tun will promote a better siphon as long as you have the lowest level of your mash tun above the vessel you are transferring to.

This can take you from a trickle to a much more favorable stream.

Another tip is to not try to eek out every last drop from your mash tun. If you are using Brewsmith, you can adjust your deadspace and allow yourself a little more room between the bottom of your mash tun and your false bottom. You will get a better transfer and not have your false bottom sucking the bottom of your mash tun.

I have made the same mistakes and as you I am now able to tell you all this from experience on my part. Once you make these simple changes, you will be surprised how much better your mash tun works.