We were having dryer vent issues for a long time. No one was able to figure out the problem. Got in touch with Dryer Vent Wizard and they sent a certified tech out. He went into the attic to see what was happening. Nobody ever went there to see what the issue was. Our dryer vents were all foil and lint was causing them to sag causing the dryer not to work. Turned out to be a pretty big job but they did it. They replaced all the foil with solid metal dryer vent ducts. The issues we had has been resolved. They truly are the Wizards.