Fin tube ceiling convectors

Christian Egli_2

Data I have of a 50's era steam system with 2 inch Vulcan radiation steel fin tube placed high up the walls gives me these ratings: 1 row - 12 ft long - 63 EDR; 2 rows - 12 ft long - 113 EDR. I don't remember the fin per foot count, here they are about a 1/4 inch+ apart. Check out Slant Fin catalogs, these type of radiation are still very much modern.

Those numbers are for heating with steam. Keep in mind steam is powerful stuff, you don't need much radiation to get an effect you can feel. If you plan on using half as cold water, you're most likely going to have to think about doubling your EDR square footage. You'll definitely need to look into this.

If you don't, this big idea of using condensing boilers and a really cold heating fluid might quickly be overridden by the user. In order to get hot and feel the heat from the current ceiling radiation your system will call for a hotter heating fluid. Contrast your existing small fin tubes to low heat ceiling radiant panels that necessarily cover the entire surface available. I'm not sure this is what you are talking about doing.

Another issue.

Steam cavities are large. Once filled with water, these make the system much more sluggish, slow to respond on a call for heat, and what's worse, prone to causing overheat. Once you stop the boiler, you've still got loads and loads of heat in your huge water mass. This overheating will be a major source of inefficiencies and a costly waste of fuel, in spite of your condensing boiler. All this is not true in a steam system, which, in your situation is a remarkably agile heat.

See where I am going?

Steam systems are not particularly clean either. Your radiation pipes are likely cluttered with crud. My experience looking into these steam fin tubes would lead me to say that on average, you can extract a whole half-gallon of dried up dirt from one 12 foot section. With a hot water permanent flush conversion, where do you think this crud is going to cause you the most trouble?

This crud piles up in the fin tube just like it does in a radiator because there usually is a little step up on the outlet fitting that holds back some water and the dirt. No problem. On the other hand, distribution pipes that drain themselves dry stay remarkably clean.

I would really consider staying with steam. It works with more agility than any other system. For boosting efficiencies, I would first look into repairing / replacing all the traps. With the boiler change, depending on how big and worthwhile the scales are, installing an economizer would achieve the extra boost in combustion efficiencies you are looking for. This can be done to your existing boiler assuming there is nothing wrong with it.

I hope this is helpful.

Scott Kohler_2

Ceiling mounted fin tube(steel) convectors

I'm looking at an old youth detention facility w/ ceiling mounted fin tube convectors. The idea is to re-use these convectors but the problem is a lack of resources f/ determining the output capacity of these convectors. If anybody has a clue how I can size these things i'd greatly appreciate it. I forgot to mention this is on a steam system that the new bulding owners want to convert to water so we can use condensing boilers.

Ted_13

Scott Try this....

Scott try this sterling commercial specifier
(http://www.sterlingheat.com/sterlingfte/Select.aspx)
Click on the select button on the enclosure type. you probably want double slope cover?

is "condensing boiler" the new customer buzz word ? Why waste your money on a condensing boiler for this type of system. in order for a condensing boiler to condense flue gas the return water temp must be 140º or lower. The ideal range is 100º-140º, this water temp does not work well with fin tube. I would suggest an 87% efficient boiler will provide just as as much efficiency as a condensing boiler on the same system at less capital cost and likely less maintenance cost.