Fin tube ratings

Dave0176

Hi all, I unfortunately ran into a one pipe boiler replacement where the HO removed most of the CI radiators and replaced it with slant fin steel 1-1/4 baseboard in the standard type baseboard enclosure. He said they had this done in 1968 so they been there a while. The longest run is the dinning room at 10 ft. I need the steam output ratings for these.

I asked if they hammer and he said the dinning room one does sometimes. Anyway I got make sure steam velocity is kept super low keep these as quite as possible. Their both 80 yo so the baseboard will be staying.

Jamie Hall

You can get pretty darn close with arithmetic -- find the area of a fin (count both sides! -- subtracting for the pipe) and then count the number of fins per foot and multiply -- and that will be pretty close to the EDR per foot (do all this in feet and square feet, of course).

JohnNY

Hi Dave,
I'd do this: BTU/ft ÷ 240 = sq. ft. EDR
Best,
John

Dave0176

Thanks guys appreciate it. I figured what they have, it’s the multi pack 80 style with steel fins so according to slant fin 990 btu, regardless, the boiler size I chose is the right size.

EBEBRATT-Ed

I was going to suggest just looking up some baseboard. For a given pipe size and fin area that would be close enough. What @JohnNY & @Jamie Hall suggested is fine although the "bare ratings" @JohnNY gave you will be reduced by the baseboard enclosure.

If the long one bangs you could make it two pipe if you can drip it to a wet return or drop a loop to the floor and come back up in the bottom of the steam main..........but you already know that

Dave0176

EBEBRATT-Ed said:

I was going to suggest just looking up some baseboard. For a given pipe size and fin area that would be close enough. What @JohnNY & @Jamie Hall suggested is fine although the "bare ratings" @JohnNY gave you will be reduced by the baseboard enclosure.

If the long one bangs you could make it two pipe if you can drip it to a wet return or drop a loop to the floor and come back up in the bottom of the steam main..........but you already know that

Ed I appreciate the thoughts and yes I am familiar with running baseboard on one pipe steam, that being said the HOs are in their 80s the baseboard has been there 50 years they just want me to replace the 70 year old boiler.

JohnNY

EBEBRATT-Ed said:

although the "bare ratings" @JohnNY gave you will be reduced by the baseboard enclosure.

I'm not so sure that's right. Often, the enclosures influence convection and therefore heat output. I don't know how the manufacturer determined these ratings but for a quick EDR calculation, I'd think you could do a lot worse than using the (given) BTU-to-EDR multiplier.

EBEBRATT-Ed

@JohnNY you are correct.

I was thinking wrong on that one. The baseboard enclosure gives it the chimney effect. Bare element gives off less heat.

I knew it influenced the rating but I was wrong about which way. Sorry

Dave0176

JohnNY said:

EBEBRATT-Ed said:

although the "bare ratings" @JohnNY gave you will be reduced by the baseboard enclosure.

I'm not so sure that's right. Often, the enclosures influence convection and therefore heat output. I don't know how the manufacturer determined these ratings but for a quick EDR calculation, I'd think you could do a lot worse than using the (given) BTU-to-EDR multiplier.

EBEBRATT-Ed said:

@JohnNY you are correct.

I was thinking wrong on that one. The baseboard enclosure gives it the chimney effect. Bare element gives off less heat.

I knew it influenced the rating but I was wrong about which way. Sorry

Yep Slant Fins info gives both the bare element and the enclosure outputs. Once again guys thanks a bunch.