I do Not recommend using FF Kling! I had a horrible experience with a job that cost over 21K dollars. He installed my new boiler and didn't vent it properly. It has caused chimney failure and sickness. The gas company shut off our heat because it's a health hazard and a fire hazard. Mr Kling had expressed that he has no interest in properly venting the unit or fixing the interior damage so we have no heat. Very dangerous and they will not stand behind their work.