Outlet Placement on fabricated LLH

BillWWelds

Hi all. My name is Bill W and I am a steamfitter and welder by trade. I have been a visitor for a while, but this is my first post.

I am currently designing and installing a hydronic system for radiant flooring in my home. The heart of the system is a Navien NCB 190/060H that I received as payment for some welding repairs, (the relevance here is this isn’t something I ordered, just what i have to work with).

My question pertains to the design of my low loss header which I am fabricating. Rather than use the prefabricated navien header or make one from copper, I am electing to fabricate one from 6” pipe with 4 1-1/2” Thread-o-lets for the HWS and HWR, and Boiler Supply and return loops. With regard to this, does the placement of the outlets on this generously sized header have any effect on hydraulic separation or other performance characteristics? Specifically should they be in-line or staggered, should the boiler side be on closer centers? I am opting to fabricate this because I can. I could make it from 3” K copper but 6” pipe adds some system volume as a buffer (close to 3 gallons) and I have a bunch of 6” stainless laying around. With regard to air removal, I have a spirovent microbubble that will be placed on the HWS after the LLH and before the circulator pump. I also have a Naviclean dirt separator that will be going on the suction side of the boiler.

If i did not already have the Spirovent and naviclean, which I bought, I would have just ponied up the extra couple bucks and bought a Caleffi hydraulic separator. But because I have these items I might as well use them.

Thank you for reading, and thank you in advance for the insight.

mattmia2

With that much volume compared to the inlets and outlets the differences will be purely academic. Maybe one configuration will have more stagnation or more turbulence but practically all you might see is slightly longer or shorter run times on a heat call. I would insulate the header well, the standby loss of that volume of water will be the biggest practical effect.

mattmia2

I don't quite understand the format of your drawing, what are the numbered sections? It should all just connect to one header.

BillWWelds

Matt, thank you for the response and sorry for the lack of clarity. Those numbers were 3 scenarios for the outlets on my fabricated header: Straight, inset, and staggered. I agree you are right anything is purely academic and I am probably overthinking this.

mattmia2

The one thing I would add is a tapping at the very top for an automatic air vent, not a whole microbble air separator like you have before it but just a cheap auto vent to vent out whatever air settles out in the hydraulic separator. Caleffi and Bell and Gossett make similar to what you are building, might look at their products.

hot_rod

This is how Caleffi does theirs. What gpm flow rate are you going to be running?

If you can add at least a screen mesh inside that helps air elimination al lot. If he heads are to be welded the mesh needs to be metal. If you could build removable heads, then a composite mesh could be addd for air, on top, and dirt, at the bottom. A drain valve to flush or add chemicals.

A tapping to add a brass well to put a magnetic rod inside is another nice functioned. We sell the brass well and magnetic rods.

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EBEBRATT-Ed

Put the air removal devise on top of the LLH. That is a "slow place in the road" and the best spot for air removal

hot_rod

Some other custom builds

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