Piping a supplemental boiler to an existing hydronheating system

Mikie

Here are a few photos.
In thinking about it more, the function of the add on is to heat water and deliver it to the main boiler.

Mikie

piping supplemental boiler

I have replaced a wood fired boiler that was connected to my primary oil fired boiler.The boiler was called a "helper". Thermoststs for 4 zones (3 heat and 1 water) are on the main boiler. The only controls on the helper were an overide sensor for overheating, and another which turned on the circulator when the water temperature reached 190 degrees.
All circulators were the old 3 piece B&G type.
When the system was installed, the circulators were on the return piping (both boilers), but when a new oil boiler was replaced (about 4 years ago), the circulators were installed on the supply side, and pressure tank and spirovent were installed on the return side.
The old circulators were replaced with the Taco / Grundfos cartridge type.
There is an 1 1/4" supply pipe out of the oil boiler that goese to an 1 1/4" manifold. The circulators feed from this manifold.
The wood fired boiler feeds from a 1 1/2 " pipe, through a pressure tank and spirovent to the 1 1/4" supply manifold on the oil boiler.
There is a circulator on the return of the wood boiler which pumps into the wood boiler.
I have a basement zone (same floor as boilers) which is always air bound. I have purged it constantly, but it doesn't stay.
I think I may have put the circulator in the wrong place.
HELP!

Brad White_203

Piping Diagram?

To save some time and brain injury (in my case at least could you please post a diagram to illustrate the key components?