Low teens and windy last night. Boiler held 140 as set and burned about 70lbs. All levels of the home a comfortable 72. I pipe the water through the oil boiler where all my zones and domestic hot water are fed. Electric to the oil burner is turned off. Just use it as a mixing vessel and then returns back to the coal boiler. The circulator pump from the coal boiler to the oil boiler runs constantly. This system works great. Love the Harmon stoker boiler. Just load it and forget it for 3-4 days.
LS - coal ash should not go in your garden. I assume you mean a vegetable garden. Coal ash contains heavy metalssuch as chromium, cadmium, mercury, and even trace amounts of radioactive thorium and uranium. Not stuff you want in your veggies. I dump mine in a path through woods on my property. Packs down and makes a decent road bed. There are several internatioanl organizations whose sole purpose is to find good uses for coal ash from power plants etc. Do a google search on byproducts of coal combustion. You'll be amazed at some of the uses.