I have a quick question. We put a wood insert in our old fireplace....it is installed properly but here is the question. Our goal is to burn a fire 2-3 nights a week...not an all night fire...but just to take the dampness our of the room...this will probably last 3 months or so. Do we need to get a liner/installation in the chimney. I can see if we were burning 24x7 but not as sporadic as we plan on. They said it would cost about $1000...any advice?