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Mash tun flow rate help..

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Cajun_Tiger33

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Just built a mash tun out of a chest cooler, I tested the flow rate of it with regular tap water and I got about a gallon out ever 4.5 minutes. This seems kinda slow, what should I do to fix it?
 
What are you using as a manifold/filter/false bottom? What size ball valve did you use?

BTW, it does work better with even a short piece of tubing connected to the ball valve. Have the end of the tubing lower than the bottom of the mash tun. Talking about outside the mash tun.
 
I didn't have the tubing hooked up to the ball valve but I had the hose barb and it is a half inch ball valve with a half inch hose barb and the water was sort of just trickling out, almost as if it was only half way open. (which it wasn't)
 
Sounds like you either have some blockage, or the manifold design you're using is restricting the flow far more than it should be. What ARE you using inside the mash tun?

For my cooler mash tuns, that I made, I used the bazooka style screens. In my keggle mash tun I'm using a NorCal/Jaybird false bottom. Didn't/don't have flow rate issues with any of them. I've moved to using the keggle mash tun all the time now, for several reasons. The false bottom it has is just one of them. :rockin:
 
I'm using a CPVC manifold with 4 long pieces stretching the length of the ice chest. I don't have any pictures right now.
 
Try the flow rate without the manifold. If the flow is good, then the manifold is 100% the source/cause of the issue. You'll need to correct it before you brew with it.
 
You have blockage somewhere. I can drain 10 gallons through the grainbed in less time than that. I have a water heater supply hose conversion inside.
 
Golddiggie said:
Try the flow rate without the manifold. If the flow is good, then the manifold is 100% the source/cause of the issue. You'll need to correct it before you brew with it.

The flow rate is good with out the manifold.


Each of the 4 pieces are 16" long and I have 16 cuts in the pipe. Is that too many? And if the cuts are too wide would that have anything to do with my problem?
 
The flow rate is good with out the manifold.


Each of the 4 pieces are 16" long and I have 16 cuts in the pipe. Is that too many? And if the cuts are too wide would that have anything to do with my problem?

Never made, or used, a manifold. I've always used either the bazooka style screens (in the cooler mash tuns I've had/made) or a high grade false bottom (from NorCal). Never had flow issues with my setups either.

You'll need to get alteration advice from someone that's made this type of manifold before, with solid results. I would imagine that more slits will help the flow. Where to place them, how many, etc. is not something I know.
 
I used a chop saw to make the slits.. so they are as wide as a standard table saw blade, is this too wide? should i put them every 1/2" instead of 1"?
 
I used a chop saw to make the slits.. so they are as wide as a standard table saw blade, is this too wide? should i put them every 1/2" instead of 1"?

IMO, yes... You want narrow slits in the manifold. From what I've seen, dremmel cutting discs are used, as are hacksaw blades. You know how narrow those are, yes? Keep in mind, the most common grain crush size is .039". With your slots being many times that, you'll have major issues.
 
Does anyone have a rectangular CPVC manifold they can show me a picture of before I start cutting my next one so I don't waste materials?
 
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