Baseboard hot water question

jawman_2

I currently have baseboard hot water heat. I have just replaced my boiler, and when the contractor came out to measure my house, he told me that the baseboard heat run I have in each room, do not have the "fins" the entire lenght of the heat run. example.. 1 room has about a 12 ft run, with only about 6ft of fins. is this normal, and is it possible to "ADD" more of they fins to an existing system without re-doing all the pipe work ? is these an ADD on that I could do to get more heat into certain rooms ?
thanks in advance.

Brad White_203

Heat Loss

The amount of finned element is what you count, as you gather correctly. The heat loss of the room has to be known and compared to what the radiation can do and at what water temperature.

If the space heats now/heated before, there is your answer. Have you noted heating deficiencies?

But having more finned element than you technically need is good too, allowing you to use lower water temperatures.

There are snap-on, add-on fins, but I have never used them. I am skeptical in principle because I do not know how the contact between fin and tube is, compared to manufactured fin-tube. I really do not know and stand to learn, but tube to fin contact is everything.

Personally, when designing new systems, given that you are running the copper tubing anyway in order to connect the elements, I like to run elements longer for better coverage and lower water temperatures. Not applicable and too late for you, but a suggestion.

But the point I want to make is, regardless of the heat loss and element lengths, the elements even if over-sized, have to be proportional to the heat loss of the room served.

No point in being generous and adding 50% finned element to a room when the others on the same zone have exactly what they need. No harm on the other hand in giving the same over-percentage to all rooms, for they shall be even in temperature. Does that make sense?

One parting thought: If your elements are in series, "pearls on a string", you should be very careful when adding fins if you go that route.

Your "first room served" may seem low on finned length because it has first dibs on the hottest water. Your last room served may have extended fins to extract enough heat from diminished water temperatures.

Thus, knowing your room by room heat losses is the best, nay the only, place to start evaluating this.

My $0.02

Brad

Jed_2

Boy, what a puzzler

Short answer; yes, you can easily add fin, as long as you know the brand of baseboard you have. Just cut the pipe and add the same brand element. Some brands of baseboard require the element be oriented correctly for air flow.

Your contractor was simply measuring "effective length", or "active length", of radiation. Did the system heat properly for all rooms with the previous boiler (as Brad asked)? If so, not to worry. The contractor was just trying to get the boiler size right.

Brad's assessment, as usual, is spot on, albeit a bit more deeply analytical than needed in your case, given the lack of historical system performance parameters.

So: Do you need more element?

Jed