creating a 2 zone radiant system

Jman_2

Hi all,

I am a professional building contractor and I bought a fixer-upper house with a newer munchkin boiler, but has the old cast iron radiators. i am trying to teach myself how to do some plumbing/heating at least on my own house. i am replacing the radiators with new slantfin baseboard units and i want to create 2 zones: upstairs and downstairs. I would like to do it using zone valves and i think i understand how to do it, but how does the wiring work? Do i need a zone valve controller? Any help here would be greatly appreciated!

kpc_74

why replace...

the cast iron? Much better than the fin tube!Taco makes ZV controllers that are simple to wire. Go to their website and get the directions... kpc

Unknown

or better yet

just put thermostatic valves on all your radiators, just make sure you have a pressure bypass or even better still one o' them new fangled variable speed circs, wilo etc.
(anyone have any of the new alphas yet? they were supposed to be out by now.)

whatever you do don't do tube & fin, you will regret it.

Jman_2

when we bought our house they didn't turn the heat up high enough in the winter and it cracked all of the radiators upstairs, so i figured i may as well replace the ones downstairs too. I already installed slantfin baseboards upstairs and they didn't even through out enough heat to do anything, i just figured it was because the cast iron radiators downstairs just heated that level so fast that the upstairs didn't get warm. zacmobile, is that why you said not to use tube and fin units?

thanks again for all the help

Unknown

Mixing FT & CI is possible, but tricky

between units, but you must realize the difference.
Without a calculated HL on the existing CI (rads floor) you need to establish the water temp that "type" needs.(it may be 140F for ex.), these hold the heat longer.
You say the upper floor is now S/F BB,, were these replaced with the exact EDR as the previous CI ones?
Likely not, as wall space may have been a problem.
Replacing them all on this floor warranted a HL calc to establish a possible different water-temp (higher) flowing through them to maintain the desired room temp.
FT does NOT hold the heat very long.
If the S/F was sized(top floor) to the same EDR as the old CI ones, your best option would be to use TRV`s on every rad, constant circulation & operate the boiler at the higher of the two temps,, then you wouldn`t need ZV`s, but a PDV.

Dave

Unknown

baseboards have inherently low output for the amount of space they take up, if you go to slant fins website they have correction factor charts that will show you the actual output you will get per foot based on what water temperature you give them. If you do need to replace the cast iron I would go for a wall panel style, they work much better at condensing boiler temperatures, check out Myson, Runtal, Biasi, Dianorm, etc etc there are many choices, but again make sure they are sized for the water temperature you are using, I would shoot for about 130 deg F or so.