331camaro wrote:primary secondary pumping is the way to go! how far away is the coal boiler from your oil boiler???
The oil boiler is about 10 feet away in the house, coal boiler sits on deck in room i built for enclosing it. To get boiler fired up yesterday evening it holds about 100-120# of coal stoked, filled to where i normally do it for a 12 hour service routine. This morning i put in about 20-25 # and when i got home tonite, the bed is still deep, unburnt coal on top, good glow underneath, shook it, little bit of ash then embers. Not nearly as much burnt as before. added about another 15-20#, it will be good till morning, also bumped up AQstat to 180.
Now i need to figure out controls to get pumps to cycle/control way i want. Put an extra well in coal boiler for another stat, figuring i will need it somehow for getting circulators on boiler primary to work opposite of each other using coal boilers temp for on/off setpoints. I beleive Johnson controls might have relay in thier S350 series relay controls that will do it, but not sure. If so i only have to side plug mount in to exsisting modual relay setup(rail) and wire to circulators.