btus / foot of onix

[talasc2001]

is there a chart anywhere that will tell you the btus / ft of onix at different temps? i'm trying to size a heating system and i can't find the load of the tubing that the customer installed himself to size the pipes and boiler, thanx chris

[Christopher]

You'll probably have to use this formula:
BTU/h = gpm x 500 x deltaT
I'd imagine the deltaT would be 20, so all you need to know is the gpm and you can figure the total amount of BTUs per hour for that system.
There isn't really a BTU per foot number, since it depends on so many variables.
You might try www.wattsradiant.com/support/literature/#/wattsradiant-products-hydronic-onix/WR_Onix_Manual_Installation
and check the Appendix for some more info.