3/8 inlet 1/2 outlet..problem?

[MrStrangeBrew]

on my MLT i have a flase bottom with a 3/8 elbow on it which leads into a 3/8 barbed fitting then that goes into a bulkhead and then my 1/2 ball valve. for the outlet i wanted to use camlocks. 1/2 since all the rest of them i plan to have the same size. will the fact that it is 3/8 and restricted on the inside have any bad effect on putting a 1/2 better flowing camlock fitting on the outside??? if im not making sense please tell me.

 

[BendBrewer]

I have a 3/8" ball valve on mine and just used a fitting to 1/2" so I could attach the Cam Lock. Works fine for me. I don't pump out of the MLT full bore anyway.

 

[Ohio-Ed]

on my MLT i have a flase bottom with a 3/8 elbow on it which leads into a 3/8 barbed fitting then that goes into a bulkhead and then my 1/2 ball valve. for the outlet i wanted to use camlocks. 1/2 since all the rest of them i plan to have the same size. will the fact that it is 3/8 and restricted on the inside have any bad effect on putting a 1/2 better flowing camlock fitting on the outside??? if im not making sense please tell me.

If you are trying drain the mlt by gravity, you may lose siphon with a larger output. I would also think you "could" starve the pump if you are pumping out of the MLT wide open.

 

[Catt22]

on my MLT i have a flase bottom with a 3/8 elbow on it which leads into a 3/8 barbed fitting then that goes into a bulkhead and then my 1/2 ball valve. for the outlet i wanted to use camlocks. 1/2 since all the rest of them i plan to have the same size. will the fact that it is 3/8 and restricted on the inside have any bad effect on putting a 1/2 better flowing camlock fitting on the outside??? if im not making sense please tell me.

The increased resistance for the 3/8 tubing will definitely inhibit the flow rate. Whether or not it's tolerable only you can decide and much depends on how your system is configured. I think you are asking if there is any negative side to using larger fittings on the outside vs what you have on the inside. I suppose if you are using a pump it may be more prone to cavitation, but I can't document that. It's just a guess. I'm a firm believer in using large diameter hoses and fittings. Everything seems to go more smoothly with the bigger hoses. I use 5/8" ID tubing, but the barbed fittings have only a nominal 1/2" ID, so basically I have nothing less than 1/2" ID anywhere in the circuit with most of it being 5/8" ID. A big hose is a good thing to have.

 

[a_potter]

If you are using the 1/2 inch camlocks from bargain fittings the barb ID is more like 3/8 anyway. If you ran your pump wide open you could theoretically cavitate but you wouldn't really want to compact your grain bed like that anyway. If you wanted to calculate the exact effect on flow the formula is Q=VA where as Q(flow) is V(velocity) times A(cross sectional area of the pipe). But like I said, it probably won't matter anyway due to the camlock barb restriction.

 

[a_potter]

Actually I'm an idiot. The Flow won't change at all, just the Velocity.

 

[MrStrangeBrew]

I have a 3/8" ball valve on mine and just used a fitting to 1/2" so I could attach the Cam Lock. Works fine for me. I don't pump out of the MLT full bore anyway.

well i am going to be using a pump. so i was worried about having a little bit of air in the hose since the inside is smaller than the outside. would that cause he pump to stop? March pump. when you are draining MLT and you have the ball valve choked a little bit is your tubing completely filled with wort? or is there space in there since you arent at full flow?

 

[a_potter]

At fist you will get a tiny air pocket just downstream of the fitting and that will quickly go away and be full of wort. Think of it like a regular old racking cane. The ID of the cane is usually 1/4 inch and the tubing stuck onto it is usually 3/8 inch ID. It siphons just fine.

 

[MrStrangeBrew]

At fist you will get a tiny air pocket just downstream of the fitting and that will quickly go away and be full of wort. Think of it like a regular old racking cane. The ID of the cane is usually 1/4 inch and the tubing stuck onto it is usually 3/8 inch ID. It siphons just fine.

ah yes i see now! i think ill be safe and it will make things easier for me...i hope... and if not ill just switch it back to regular barbed fitting. thanks for the tips!