Cast Iron Radiator Project

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I just scored on 15 cast iron radiators of all different sizes. They cost $150 each. I think that is a good deal?
 
Yes. Try finding something as beautiful that will kick out as much heat and last as long for that price. You won't.
 
They are plain jane no ornamental design. But Like you said , its all about being able to use lower water temps. Perfect set up with water storage. Well next best thing to radiant floor heat : )
 
Cast iron rads are a thing of beauty both in the physical sense and in the Physics sense. Roughly half of the heat output (depending on the surface temp of the iron) is pure radiant energy warming objects not air. The other percentage, whatever that may be, is convective heating which warms the air in the room and allows it to be heated more quickly than 100% radiant. Next to a radiant slab/floor it is the most comfortable form of heat there is. Controlling the heat can be done with a thermostat which starts/stops flow by some means but to reall really let them shine and function as they are capable a person simply must use TRV's. A TRV (thermostatic radiator valve) is another device that proves God intended for us to be heated with hydronic heat instead of hot, forced air. The heavy mass of a cast iron rad and the throttling action of a TRV are a match made in heaven. The TRV will seek the balance point in a room and allow juuuuuust enough flow to match the desired setpoint. I love the feel of an idling rad on a 25* March morning, just barely warm enough to heat the room but providing glorious comfort to all in its presence. ACK I'm getting poetic about a hunk of iron for cryin' out loud. I guess there is nothing wrong with singing the praises of something that works as well as a CI rad.
 
heaterman said:
Cast iron rads are a thing of beauty both in the physical sense and in the Physics sense. Roughly half of the heat output (depending on the surface temp of the iron) is pure radiant energy warming objects not air. The other percentage, whatever that may be, is convective heating which warms the air in the room and allows it to be heated more quickly than 100% radiant. Next to a radiant slab/floor it is the most comfortable form of heat there is. Controlling the heat can be done with a thermostat which starts/stops flow by some means but to reall really let them shine and function as they are capable a person simply must use TRV's. A TRV (thermostatic radiator valve) is another device that proves God intended for us to be heated with hydronic heat instead of hot, forced air. The heavy mass of a cast iron rad and the throttling action of a TRV are a match made in heaven. The TRV will seek the balance point in a room and allow juuuuuust enough flow to match the desired setpoint. I love the feel of an idling rad on a 25* March morning, just barely warm enough to heat the room but providing glorious comfort to all in its presence. ACK I'm getting poetic about a hunk of iron for cryin' out loud. I guess there is nothing wrong with singing the praises of something that works as well as a CI rad.


Wow. That was really beautiful.
I'll have to make a note of the TRV.
 
Well said Heaterman!
Can you imagine all the CI rad's that were replaced because of poor control or bad piping? I am sure many folks just wanted to create extra space but I would be willing to bet poor controls and run away heat was the more likely problem. Nothing like a mini wood stove in every room!
 
Heaterman I could not have said it better. I love my RADs. Plus they make great towel or glove warmers
 
My wife puts the line-aired sheets on the rads in our sunroom in the winter for that last little bit of drying, and the whole room smells like fresh linen.
 
I love cast Iron Radiators too. Our most recent heating addition is a great big one. Sandblasted and freshly painted, it's awesome. It's neat that these "old tech rigs" are now the perfect radiation for Our boiler systems of today. Make sure to grab them up from all the scrap yards. Don't let them be crushed. Enjoy the Warmth.
 
It's like Christmas again!
I scored a whole flock of radiators today.
Soon I'll "love the feel of an idling rad on a 25* March morning, just barely warm enough to heat the room but providing glorious comfort to all in its presence."

A couple questions: 1- My living room is 20x16 and I had planned two rads but I got one big one that would give the BTU's. Bad idea?
2- I just really wanna be sure about question #1. I can fake the rest.
Thanks-ken
 
The heat will be more even with two. Just put them on either side of the room
 
Hello All,

I am in the midst of a master bedroom/bathroom reno and am replacing my finned copper baseboard rad in the bedroom. I'm a bit nostalgic about the old cast iron rads from the house I grew up in, and I've found some that I could get my hands on, but I read somewhere in an earlier post that you're not supposed to have finned copper and cast iron on the same zone. Can someone shed a little more light on this situation, and tell me what I should be looking out for if I am able to add a cast-iron rad to this zone? Not sure how it all goes together...I'm a novice at best. Thanks in advance for your advice.
 
They will go together and work on the same zone. The only problem is that they radiate heat at different rates, so that if you have a thermostat in the room with the baseboard, the room with the cast iron rad is probably going to overheat. Of course, if you pipe it right, you can always just turn down the cast iron rad.

It's a no-no with heating professionals, but I wouldn't hesitate doing it in my own house, simply because the cast iron rads are so nice--especially in a bathroom!
 
Thanks...a few more questions. I have 3/4" copper piping...will there be any problem connecting that to a CI rad? Also, is there a way to put a thermostat on that CI rad to shut it off if it gets too hot? Last, how big a rad do I need? The room is 12'x17' w/8' ceilings, and the rad will be located in a corner, under a window...the bathroom (since you mentioned it) is 12'x7'.
 
MissingTool said:
Thanks...a few more questions. I have 3/4" copper piping...will there be any problem connecting that to a CI rad? Also, is there a way to put a thermostat on that CI rad to shut it off if it gets too hot? Last, how big a rad do I need? The room is 12'x17' w/8' ceilings, and the rad will be located in a corner, under a window...the bathroom (since you mentioned it) is 12'x7'.



If the old fintube was adequate, guesstimate it at 600 BTU's/foot and that'll tell you how much you need. Example; if it was a 10' heater, you need about 6000btu's to heat that room.
Then use the following to find the right cast iron radiator. And if you read all the threads, you will learn about about 3/4" pipe and TRV's. http://www.colonialsupply.com/resources/radiator.htm
 
Yes, as Kenny says, a TRV will automatically control the temp. And yes, 3/4-inch copper is fine for most radiators. As to the question of whether they fill all the way with water: they should. If not, you're not venting them correctly and they won't heat properly. A ci rad should be full of water with no air.

EDIT: A ci rad in a hot water system should be full of water. In steam systems, it's a whole different process. Same radiators in many cases--just a completely different way of transferring the heat internally.
 
Just picked up this beauty up in Rochester, NY while there for bowhunting. It cleaned up nicely, no leaks and fills in that blank space where the pellet stove used to live. Oh, and there is three less deer in NY out of a herd of 900,000.
 

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trehugr said:
Just picked up this beauty up in Rochester, NY while there for bowhunting. It cleaned up nicely, no leaks and fills in that blank space where the pellet stove used to live. Oh, and there is three less deer in NY out of a herd of 900,000.

Beautiful piece of cast iron...three less deer with magnetic antlers to run into the side of my truck!!
 
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