Manifold pipe size?

[bunker45]

Why is everyone using 1/2 inch copper instead of 3/4 copper to make their manifolds? Is it a price thing or a flow problem I am not thinking of. Thanks

 

[vincentAlpha]

Hmm, for me it was ease of getting and working with the material (1/2" CPVC). I suppose you could go larger and achieve greater flow rates but I think that gets you into other issues like channelling(not sure on that though). I'd also think if you built a manifold using 3/4" the same was as you would a 1/2" you'd wind up with more deadspace in the tun since you lose suction once the slits in the manifold are above the waterline.

 

[Dog House Brew]

I can't see any advantage to 3/4. 1/2 give plenty of flow and speed isn't the main factor. Generally a manifold is for fly sparging and your flow is a trickle. If your a batch sparger I would rather use the stainless braid. I've done both, and I use a manifold made of 1/2. I do batches from 13-18 gallons and found fly sparking to be the best. Plus when I recirculate my pumps are 1/2 anyway. Just my $.02. Now if I were doing bbl batches with larger pumps I could see 3/4-1".