Flyer5 wrote:You may be able to powervent the oil unit. Then use the chimney for the coal. That would probably be the safest route.
I'm hoping to not need to burn oil at all.
My coal kitchen range can only heat the back part of this 17 room Victorian.
Electricity is cheap here, so I had it upgraded to 400 amp service and then I installed an electric plenum heater and controls in the oil furnace duct work. Now, the oil burner only comes on for make up heat when outdoor temps get down near zero.
With the Oak 118 to heat the front half of the house, I shouldn't need the oil burner at all, unless I'm away from home longer then the 118 takes to burn a load of coal. And even then, the oil burner's only coming on when it gets so cold out that the electric heat can't cope.