Ok, being new to boilers, wood aaannnddd plumbing is very difficult. but thanks to all for their guidance through this forum. There has been alot of discussion recently about pump sizing from long run boiler to house. I understand the info I need to figure this out however at the final hour I have decided to add a sidearm therefore changing my Btu requirements. I just dont know by how much. So that is my question, how many Btu's should I expect to add to my system for a sidearm or do I need to even concern myself with this? Thanks, Joe