slow run off

[macleanb]

This may sound silly but I was getting slow runoff with my old picnic cool box. What it turned out to be was that I was shoving the small plastic tubing that connected the manifold to the tap too far up the manifold at the t-piece and restricting the flow through the manifold

I had this problem too - I ended up cutting the end of the tube so that even if push right in there was still a gap.

[Matt]

Did you have a lot of water above the grain bed?

Was thinking this today. Was more than usual this time to get temperature right. This never a problem in the old m/t.

I've had this, I think the weight of the water compacts the grain bed.

[Dennis King]

got a felling this was the problem

[hoppingMad]

got a felling this was the problem

I'm not so sure. I used to get the odd stuck sparge, untill I reverted back to what I had been told, which is to keep the grain bed submerged.

Now, even with a finer crush, I have not had a single stuck sparge since keeping the grain bed under at least an inch of water. I also runnoff very slowly during my fly sparge ie 26 litres in 70 minutes. My eff. is typically 83-85 %

I let the water level begin to drop late in the lautering so that there is virtually zero water remaining in the bed right on the 26 litres collected. (not counting grains absorbtion)

[agentgonzo]

I've had this, I think the weight of the water compacts the grain bed.

The opposite happens. The grain bed compacts if you don't have enough water in the lauter tun. You should keep the level of the water about 1" above the level of the grain bed. The water provides buoyancy to prevent the grain bed compacting.

[Matt]

IIRC I've had probs with too much or too little water in the grain bed. I've had stuck sparges when the water builds up to say 2 inches above the grain bed.

[Jim]

The problem boils down to 4 things as far as I can see:

1. Crush of the grain

2. Drainage capability of the mash tun (hole size, number of holes etc)

3. Compaction of the mash (depends on how long it's been static in the tun, and the amount of water used)

4. Temperature - the sugary solution will be more viscous at lower temperatures.

So really, you need to get all of those things right to get a good run off.

[Dennis King]

As a quick follow up to this thread, just finnished mashing today and it was fine. Run off was just under the hour. Used less water this time, that was the only diffrence.