Converting Monoflo baseboard to Series/split?

Adam_Alberti

HI, Long time reader, first time posting.
Looking to do a repipe of my Monoflo system to gain headhight in the basement. Looking for the best way to go as far a piping. Did a lot of reading but wanted to get some opinions if I could. Was planning on using O2 Pex (size depending of how its piped)

Current System works well. No real cold spots
2000 sq fr Cape on Long Island
6 year old Peerless oil burner.
Taco 0015 IFC feeds main line
Taco 007 feeds just LR(9'BB and 9K BTU rad)
Updated windows and insulation.
Burnham baseray 7" CI baseboard throughout 1 st floor
CI rads upstairs (one in downstairs LR as well)

Thinking or doing a series run or maybe split series.
I attached some pics of some ideas, any feedback would be greatly appreciated!

1st idea- series run.
My concern if I would lose too much heat by the end.
Thinking 3/4" O2 PEX
I would run the 007 for the upstairs (3 rads- 17K BTU) and the 0015 would run 2 zones on main level(61' BB and LR (9' BB and 9k BTU rad)

2 idead -split series. Make first floor one zone that feeds into 1" O2 pex return. 2nd floor either do series or split as well?

Open to others ideas of course
Thanks
Adam,

EBEBRATT-Ed

I would leave it the way it is. A series system the water looses temperature by the end of the loop where a mono flow system usually looses less temperature. If you convert it to series you may have to add more baseboard near the end of the loop

Adam_Alberti

I’m finishing the basement and I would gain 8” in height so I really would like move the pipes. So maybe the split zone then

Ironman

In either proposed scenario, the system performance will not be as good as it is now.
If 8" of headroom means that much to you, why not just raise the existing pipes?

Adam_Alberti

If I slam the main line to the joists and shorten all the risers I cold
Prob get another 4” or so. Seems like a lot of work for a few inches. I would definitely prefer to just repipe it if I doing that much work already. I would be up for different options as well. Manifold system maybe?

Ironman

That would work better than a series loop. Probably more $$.

What am I missing that raising the monoflo wouldn't give you more height but a series loop would?

Brewbeer

I re-piped a mono flow system when I finished the basement of my last house. It was 1 inch copper with 1/2 inch take-offs. I kept the set-up as-is, just raised the main loop up into the joist space. I measured and drilled each joist from the basement so they would all line up perfectly, and then drilled holes through the side of the house in alignment to feed the long lengths of copper through the holes in the joists and cut to length.
Even re-used all the 50+ year old cast copper monoflow fittings.

Adam_Alberti

Hi @Ironman
I would be able to run everything in the joist space rather than below. Then I can Sheetrock right to the joist.

And @Brewbeer
My setup is all black pipe (2” I think) and cast monoflo tees

Adam_Alberti

So I did some more reading and thinking manifold is the way to go. Would it be a problem to have baseboard loops and rad loops on the same manifold. I would prob use same size pex ( thinking 1/2 would suffice)

Ironman

Are the BBs and the Baseray currently all on the same SWT? If so, how well does that work?

Adam_Alberti

Yes. All bb and rads are 180. House feels pretty good. One bedroom gets a little warmer(has 20’ bb). But overall even. Thinking about possible adding basement loop as well

HVACNUT

Homeruns from each rad back to new manifolds at the boiler.

Adam_Alberti

Thanks! Looks like that’s the consensus. I was actually just looking at a Caleffi manifold. Does it matter if I have bb and rads going to same manifold? If the heat is balanced between loops?

Adam_Alberti

I meant to say similar heat load on each loop

Ironman

Adam_Alberti said:

Thanks! Looks like that’s the consensus. I was actually just looking at a Caleffi manifold. Does it matter if I have bb and rads going to same manifold? If the heat is balanced between loops?

If they're playing well together now, then putting them on the same manifold won't change that.

Adam_Alberti

Thanks!!! Appreciate the info everyone!!

hot_rod

I'd vote for a home run system also. It would be the easiest to retrofit and clean up the basement issues. Individual flow balance is also nice to dial in the perfect comfort range.

hot_rod

If you want to zone now or in the future a pressure bypass can be added to the Caleffi manifold, better yet a ∆P circulator

Adam_Alberti

Great info. Thanks hotrod👍