After installing a add on wood burning furnace we noticed a few things that we have questions about. First, there seems to be some sort of black liquid dripping down the pipes and the second is how high should the chimney be out of the roof of the house. We thought that maybe we did not have it high enough and that is why we have the black liquid.

Welcome to the wonderful world of wood heaters and creosote. Only use very dry hardwood and keep the fire hot. Otherwise, creosote will build up and you will have a chimney fire. Periodic cleaning in a necessity.