Was able to do a Routine Maintenance & Tune Up on a 27 year old Ruud Natural Gas Furnace in the Wilmington, Delaware area. Definitely showing its age in some corners, but it is still kicking safely produced heat! They truly don’t make them like they used to and units like this prove that point every single day. Thank you Paul for allowing us in your home and trusting us with your comfort. Any questions or concerns you may have, you know who to call! Thanks again