Anderson 837 balance - what weight does it support?

Hello there. In general, we don't identify Andersen balances by the sash weight, since in the case of these balances it depends heavily on the window dimensions as well. In general, the most reliable way to know what replacement you need is to remove one of the old balance boxes and send us pictures of all the stamps on its surface. Some clump of numbers will tell us the replacement you need. You can read more about Andersen balances here.