Abstract: An inspection chamber for use in sanitary sewer systems has an integral back-flow prevention valve. The valve can be installed through an access pipe with the inspection chamber in place underground. The valve does not interfere with the installation or removal of a plug in the inspection chamber during construction and inspection of the sewer system. The inspection chamber comprises a clip oriented to receive a valve member from the direction of an access port. The valve member comprises a pin connected to a flap member by a narrow bridge member. The flap member has a projecting handle member. An installation tool holds the valve member by the handle member and provides a tab which can be hammered downwardly to snap the pin into the clip thereby securing the valve member in the inspection chamber. An inspection chamber according to the invention avoids the necessity of providing a separate buried back-flow prevention valve.

Abstract: An inspection chamber for use in sanitary sewer systems has an integral back-flow prevention valve. The valve can be installed through an access pipe with the inspection chamber in place underground. The valve does not interfere with the installation or removal of a plug in the inspection chamber during construction and inspection of the sewer system. The inspection chamber comprises a clip oriented to receive a valve member from the direction of an access port. The valve member comprises a pin connected to a flap member by a narrow bridge member. The flap member has a projecting handle member. An installation tool holds the valve member by the handle member and provides a tab which can be hammered downwardly to snap the pin into the clip thereby securing the valve member in the inspection chamber. An inspection chamber according to the invention avoids the necessity of providing a separate buried back-flow prevention valve.

Abstract: An inspection chamber for use in sanitary sewer systems has an integral back-flow prevention valve. The valve can be installed through an access pipe with the inspection chamber in place underground. The valve does not interfere with the installation or removal of a plug in the inspection chamber during construction and inspection of the sewer system. The inspection chamber comprises a clip oriented to receive a valve member from the direction of an access port. The valve member comprises a pin connected to a flap member by a narrow bridge member. The flap member has a projecting handle member. An installation tool holds the valve member by the handle member and provides a tab which can be hammered downwardly to snap the pin into the clip thereby securing the valve member in the inspection chamber. An inspection chamber according to the invention avoids the necessity of providing a separate buried back-flow prevention valve.

Abstract: Apparatus is disclosed for maintaining the temperature of waste water entering a grease trap below a preset temperature. The apparatus is useful to prevent grease which has collected in the grease trap from being washed into the sewer system by persons attempting to flush the grease from the trap with hot water. A temperature sensor monitors the temperature of waste water flowing into the grease trap. Cold water is introduced directly into the waste water conduit, upstream of the trap, through a valve controllably coupled to the temperature sensor whenever the temperature of waste water in the waste water conduit exceeds a threshold temperature.