pick-up allowance

Phil_6

is usually built into the net rating for the boiler

mpc

pick-up allowance

We measured the radiators for edr and calculated the capacity of our system to be approx 45,ooo. Read about the pick-up allowance of 33%. Does that mean we need to get a boiler with a capacity for 60,000 load rather than 45,000
because we need to add the pick-up for the pipes? or am I interpreting this incorrectly? thanks in advance for your help. ja

Maine Doug_23

Pick-up allowance

So the pickup allowance grows with the size of the boiler? As they get larger and heavier they need bigger trucks?
This would also explain the arms on Mad Dog.

thfurnitureguy_4

Joan,as I understand it,The NER I=B=R rating allows for normal insualted piping. If the boiler is far away from the area you are heating or you have other non normal conditions you will need to allow for more pick up factor. for normal installs the net figure is the amount of EDR of your radiators.

Bob W._3

Look at a ratings chart for a boiler, like this one:

http://www.weil-mclain.com/netdocs/ratingseg.htm#RATINGS

Notice there is an AGA input rating, a DOE rating and a rating for the amount of steam supplied (IBR rating). There is also a rating for the sq. ft. EDR. That is the one to compare to your system, as it has the pickup factor built in, assuming normal piping.

Thus, an 75,000 BTU input boiler has a DOE rating of about 61,000, and will drive 192 Sq. Ft. of steam, about 46,000 BTU per hour.