Welcome! Here are the website rules, as well as some tips for using this forum.

# Double tube copper fin baseboard

Options
Member Posts: 4
This is in a church hall built in the 70's. 3/4 copper in with ubend on other side returning in same fin. Anyone know the BTU rating on this. 14" cabinet, 2 1/2" hign x 5" fin. Assuming 180° water input 2 GPM? I've found older articals but they sound like 2 separate fin. This is 1 fin

• Member Posts: 23,442
Options
You can get remarkably close to the EDR of that thing: determine the area of one fin, counting both sides. Subtract of the area lost to the pipes. Convert to square feet (divide by 144). Now count the number of fins per foot and multiply -- that will be pretty close to the effective EDR.

Then looking up the BTUh per EDR for 180 F water, multiply, and off you go.
Br. Jamie, osb
Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
• Member Posts: 7,379
Options
That doesn’t look that different in size/surface area from Smith’s Heating Edge. Look it up and you can compare the output charts for that.

I would guess around 800 btus per foot when piped like that with 170* AWT.
Bob Boan
You can choose to do what you want, but you cannot choose the consequences.
• Member Posts: 4
Options
There us a U bens on other side. So one pipe is supply and the other return. Will that matter?
• Member Posts: 4
Options
I’ve never seen the Smith product. It has more sheet fin and is vertical not horizontal. Also I have a 14” cabinet. The tall cabinet should give more BTU but should be close to the smith product with more fin volume. Thanks
• Member Posts: 4
Options
So using the EDR method. Fin is 2.5”x5”= 12.5 sq in minus 2-3/4” tube (2x.6=1.2 sq”). 12.5-1.2=11.3 sq in per fin x 40 fin per ft= 452 /144sq in per ft=3.14 sq ft of fin x 240= 753 BTU per ft. Which is also close to Smith BB.
• Member Posts: 7,379
Options
240 is for 215* steam. Use 150 for 170* AVERAGE water temp.
Bob Boan
You can choose to do what you want, but you cannot choose the consequences.
• Member Posts: 3,113
Options
Isn’t that 240 x Edr for steam I think for hot water it’s edr x 180 For btu peace and good luck clammy
R.A. Calmbacher L.L.C. HVAC
NJ Master HVAC Lic.
Mahwah, NJ
Specializing in steam and hydronic heating
• Member Posts: 7,379
Options

There us a U bens on other side. So one pipe is supply and the other return. Will that matter?

Yes it will. It will lower the AVERAGE water temp.

Bob Boan
You can choose to do what you want, but you cannot choose the consequences.
• Member Posts: 1,194
Options

There us a U bens on other side. So one pipe is supply and the other return. Will that matter?

Lower pipe should be return. As mentioned, it allows a larger temp drop for the same length of radiator and lower flow rates. You can get a little more boiler efficiency and smaller pump that way and both supply and return are on the same end.

As you will see in the Smith chart, there is some different in output depending on how it's piped and flow rate.

I think Monoflo setups require being piped that way to maintain low flow rates and stratification of the water in the pipe.