Hi everyone. We bought a house a couple months ago and while we had a general inspection I didn't have the fireplace/chimney inspected by a chimney sweep/inspector. The inspector said the fireplace hadn't been used in at least 5 years. The gas logs were installed by the owner before the previous owners. The previous owners said they had not used them in their ownership which was about 6 years. We're going to go through a cold snap this week and I would like to be able to use the fireplace if safe. I swept it as best I could to get the loose flakey stuff out but there seems to still be some more hardened tar in the flue. There are no cracks in the flue from what I can see. My question is would I be ok to run this fireplace in its current state or does it need a full professional cleaning? Thanks for your input!