Mike, Another thing about the dryer is that it looks like the 4 inch vent is adapted down to a three inch rigid vent pipe. I don't know where the vent travels on its way to the outside, but if you ever have the chance to increase the whole run to 4 inch rigid pipe, it should be done and, at the same time, the flexible duct behind the dryer should be greatly shortened or eliminated. It will mean removing a clamp before you can pull the dryer out for cleaning or service, but all of that vent tube behind there is not safe. Any restrictions in an electric dryer's vent system can cause early failure of the heating elements because they run hotter with the restricted air flow over them. This can be a factor in dryer fires, too. You want to keep this beauty working right for many years like all owners of fine appliance treasures.