Wastewater Combination Air Valve with Outlet Pipe to Drain

[CivilizedPE]

We have a wastewater combination air valve (CAV) installed on the discharge side of a lift station equipped with submersible pumps. The client would like the outlet of the CAV piped to a sump at the other end of the room. The client's concern is that when the valve releases air it will release sewage with it. The outlet on the CAV is 2" in diameter and is located about 3 feet above the floor. The drain piping leading to the sump would be routed down to the floor, run against the wall to the sump resulting in approximately 30 ft of drain pipe. An air gap would be provided between the drain pipe and the sump.

Has anyone used a similar arrangement? If so, can you provide a picture? Also, are there any concerns with the valve operating properly given the long drain pipe on the outlet? Thanks for the input.

 

[bimr]

The valve would work fine in the arrangement suggested by the client.

The preferred arrangement is to delete the valve entirely. These valves should not be used if possible because the valves will not seal. See the attachment.

You should design the installation so that the pipe remains full at all times once you have commissioned the system.