UHRIG’s Therm-Liner can be installed both in existing sewers and in new ones. The basic requirement is that the sewer dimension is at least 400 mm. Smaller sewers do not carry enough wastewater and the installation of the plant becomes complicated because of the size. Alongside classic gravity sewer systems there are also wastewater pressure pipes which cannot be walked through. Wastewater heat can also be recovered in pressure pipes of this type, but generally the heat exchanger must be tightened around the pressure pipe, or the pressure pipe must be replaced by a pipe section in which a heat exchanger is integrated. Pressure pipes are generally used for energy generation if the heat exchangers are installed at the same time as a pressure pipe is restored or installed for the first time. Ultimately, an individual inspection is necessary and advisable for every project.