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Connecting an Oil furnace to coal furnace
I have an existing Buderus oil fired hot water baseboard system in my house. I would like to pipe a Keystoker KA6 boiler in series with the existing system. I was hoping to find a diagram or pics of how it has been done. I’d like to keep the existing system when I will not be able to feed the coal system when I’m out of town etc. Any thoughts, info or pics would be appreciated. Thanks