Our new home has oil heat which is one of the primary reasons I'm so interested in installing a wood add-on furnace. However, it's of course important to keep the oil furnace in good working order. I recently got a price quote of 275.00 for "annual service." What does this entail? I'm a pretty handy guy, so if I can get the parts and there are no specialized tools involved, can I do it myself? I know that the filter needs to be changed, but what else? Where can I get parts?