Did you know that Hot Tubs Require Maintenance? By: Sean Struckmeyer | Tech Inspect Home Services Hot tubs are interesting vessels and have a lot of components that are not readily visible. The shells and layouts come in a multitude of designs. They are made from a mixture of fiberglass shells, wooden frames and lots of pipes and insulation. All that said, they do have some common components, such as the filtration system, heater, jet pumps and circulation pumps. Depending o