What Squsre feet of steam for a 3' * 3' *3' block of cast iron

Gene Cataldo

I have 7 ceiling mounted blocks of cast Iron which are wrapped with duct work, this duct work delivers the steam heat through these ducts. I need to know how many square feet I need to allow for in my calculations.

Thank you

Gene

Mike T., Swampeast MO

Sounds like an indirect heating system. Presuming they're using the typical "pin-type" indirect radiators I come up with somewhere between 405 and 495 sq.ft. EDR that could fit in roughly that area.

There should be some sort of inspection door. Can you get a decent look inside to count sections? 36" is the length of nearly all these type of indirect radiators, but they were made in various widths and heights. Height ranges from about 9" to about 15 1/2", so if you have about 36" of height they're almost certainly stacked. How many stacks? How many sections per row? How wide is each section? If you can reply with those numbers I can give you a much closer estimate of the EDR.

If you don't already have Dan's book "How Come?" (available here), I'd really suggest you buy it before doing much work to an indirect system. They're rather amazing beasts that actually rely on quite high infiltration to the structure to work. Fresh outdoor air provides the input and for the system to work properly indoor air has to exit the structure. "Tighten up" the structure and you can drastically reduce this flow of air.

DanHolohan

This will help:

Indirect radiation

It pays to wander off the Wall.