Using existing controls for add on coal boiler

Thanks, theres a leisure line dealer in Nashua, NH, maybe I'll go talk to them. My friend likes his.

Have a question regarding the second circulater pump between the two boilers. Do I have to pipe in a bypass so I don't burn it up when the main circulater that sends water to the zones is off? Look at a few piping diagrams and see nothing of the sort. Thanks for the help.