boiler for steam radiators, boiler for hot water baseboard?

[thecoalman]

Originally Posted by Coldjensens

Just google "are cast iron radiators more efficient than copper baseboard. "

Firstly you need to define what you mean by "efficiency". Are you talking about heat transfer or using less fuel?

1. Copper will have faster transfer of heat, there's no way around it... it's simply a better conductive material.

2. There is no fuel savings with either metal, a BTU is BTU and it's going to heat something.

3. Radiators or steel baseboard will have better "comfort factor" which is what I think you're confusing with "efficiency". They can store more heat and because the heat transfer is slower provide or more even and constant heat.


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Lets put this into different context, you can buy electric baseboard that is either direct element or hydronic. If you want to maintain a temperature of 70 degrees it's going to cost you the same for either system because you're going to use the same amount of electric. The difference is the hydronic will be a more comfortable heat because you won't have swings in the temperature. It provides a more steady heat because we can slowly put heat into the space stored in the water instead of doing it all at once like you have with a direct element heater. .

[bradykp]

hey, thecoalman, can you please go take over another thread? your little debate on the side here is adding zero to the question i asked.

[thecoalman]

Originally Posted by bradykp

hey, thecoalman, can you please go take over another thread? your little debate on the side here is adding zero to the question i asked.

I've only have two posts in this thread regarding cast vs. copper and It's not me that has brought up the subject, it's a public forum and when misinformation is passed around it should be corrected. People might be finding this thread forever through search engines.... Having said that as you request I'll leave it alone, have a nice day.

[chet everett]

The "wisdom of google" sometimes is fine, but when the material science is contrary that suggests the question is not being asked properly.

As coal man said, if you have a heating plant that makes steam or hot water thermodynamics cannot ne changed -- heat flows from hot to cold and every pipe or radiator will help to get the heat to the cold.

In a retrofit situation the key is to tune the behavior of the heating plant (there are many variables including temp of the water, pressure / flow of the water and run time for the circulator) so the new plant is as comfortable as the old. There is pretty much no way that the burner would use more fuel if radiator side is transferring the heat from the water to the air more quickly, nor would a properly tuned heating plant use any less fuel if a material that transferred the heat less quickly is used...

If you prefer the look of old fashioned radiators or if you want baseboard radiators or if want "Euro style" steel radiators or even if you decide to use underfloor radiant hydronic tunes / panels you won't use more or less fuel with a well tuned heating plant.

There are some caveats. Old fashioned steam heating plants run at over 200 degrees F, some at 220 or more. That is a lot of heat energy. The relatively slow heat transfer rate of cast iron helps to moderate that blast. Modern hydronic systems typically run at much lower temps. Much more radiating area and/or radiating devices with better heat transfer characteristics allow the smaller heat content to be extracted into the heated space. A somewhat related behavior is also true with underfloor hydronic heat -- layers of old flooring can essentially trap heat and make it impractical in retrofit situations. No sane person would call hydronic underfloor heat "less efficient" than cast iron radiators however if the flooring is isolating heat the home will take forever to warm up and smart heating installers / retrofit consultants will recommend against this is such situations not because of "efficiency" but impracticality...

[nagpuri]

Did you finally do the conversion? If yes, how much did it cost?