Thanks a lot for your reply. Quick questions, where would I need to add check valves and whats the purpose of them? There isn't any in the system that I see at this point.packard bill wrote:It looks as if your house was originally fitted with a gravity hot water system. With a few check valves you should be able to tie right in the system. Forced hot water systems did not appear until the advent of stoker, for quick recovery. If you decide you need a pump, I'd recommend one of the little 3 speed pumps from B&G, or Grundfos. Use the lowest speed. Otherwise you'll need to install a bypass loop. I do think you'll be alright as a gravity system since I think it was originally set up as one. Have your return split in two so one half return water goes into one side of boiler and the other half of the return water goes into the other side.
If you're using a oil-fired forced water boiler, you're heating a tremendous amount of water due to the size of your supply and return mains (from an old gravity system), you caan still use the oil fired for backup if the gravity system isn't enough when it's zero degrees out.
You'll be regulating the house temperature with the water temp. so when it's warmer out, you'll cut back on the water temp in the boiler.
I would insulate and skin the boiler with sheet meatal to keep the heat in the boiler, unless you want to heat the basement as well. Hope I offered some help. Good luck. PB
I think my plan is to shut the oil boiler off and shut the water flow off to it unless I need it to help during very cold nights. I'm going to have to wait to finish this system in the warmer months because there is a few connections I can't get apart and one ball shut off that won't shut off. Guess I'm going to have to drain the whole system this summer.