EDR of Steam Mains

Ban

We are trying to figure the total EDR of our building and are having difficulty with figuring out the main on this particular system. We calculated the EDR of our radiators to be 1146 sq ft. If the pick up is .333% for the mains, that would leave us with 378 sq ft.



The system is a one-pipe with a 4" main and we have evidence that it used to be on a district steam system. The main is run in a near full-circle around the building to the boiler, as seen in the photographs below. Half of the main is a counter-flow and the other half a parallel-flow. We are concerned that the main might be so large that we need to account for more then .333% so we are trying to determine the proper EDR for mains. We cannot find any solid information on how to determine this. The entire loop of the main is currently insulated with 1" fiberglass and is approx. 125' long.



Advice is appreciated.

Charlie from wmass

edr is surface area

so figure the surface area of your pipe.

Ban

Ok

Are you referring to the inner surface area of the pipe or the outer? How does the insulation factor into calculating a proper EDR? Is there a good publication that has all of this information complied?



Thanks.

Mark N

Pick up

The pick up is also the run outs and riser. I would think it also is the energy needed to heat up the boiler to make the steam and all the near boiler piping.

Charlie from wmass

Lost art of Steam

has all the answers you seek.