how many radiators

sean_2

hi,i am installing an aqua-therm outside wood boiler to heat my 2000 sq.ft.house and 1600 sq.ft.shop.it is the big model 345.my runs are 125 feet.i have an existing fuel oil boiler system in the house already and will tie into that existing system.the shop is going to be on a seperate system
i was going to heat that w/cast iron radiators that i salvaged from old houses. 2 units i have are 3 feet long
11" wide and 18" tall.the 3rd unit is 5 feet long 10" wide
18" tall.the brand is "american".i was wondering if i will need more than this to heat the shop.it is 40'x40' with a
10'ceiling and well insulated. we are located in southern wisconsin.the system uses 1" pipe and a taco #7 pump.the system will run at 15lbs.pressure and 160 degrees
thank you,sean

Mike T., Swampeast MO

It all starts with heat loss...

www.hvaccalc.com

You can get a "limited time use" but fully functional program for a nominal cost. EXTREMELY easy to use and figure out. You need nothing more than the ability to use a tape measure well, make a simple sketch of the structure, and fairly common construction/heating vernacular.

From there you just have to determine the "EDR" or Equivalent Direct Radiation value of your cast iron radiators. You can find tables on this website suitable for many columnar and tubular cast iron rads.

Then just print out the first part of my long series of posts under the topic "Sizing Radiators" with the output table and example for a sample space at various iron temps (and outputs). Very simple math there. Don't concern yourself with the rest unless you're just curious or enjoy bizarre theory. DO THOUGH pay attention to the fact that those tables are based on a 70 degree space! In a shop you may well want a temp significantly lower and such will have a significant effect on the amount of iron required.

Of course you can always buy a book on heating design (fairly old) and compute the heat loss manually...