What is the simple test to check the venting system during drainage from a fixture?

The simple test to check the venting system during drainage from a fixture involves listening for gurgling as the last bit of water leaves the drain, along with checking for the presence of sewer odors. This approach is effective because gurgling sounds can indicate that air is being displaced in the venting system, suggesting that there may be an issue with proper air flow or venting. When a fixture drains, the water should flow smoothly, and if it is creating gurgling noises as it drains, it can signal that the venting is not functioning as it should.

Furthermore, the presence of sewer odors serves as another critical indicator. A properly functioning venting system should allow sewer gases to escape safely through the vent pipes. If odors are detected, it can mean that the vent system is blocked or inadequately set up, which could lead to potential health hazards and decreased functionality of the plumbing system.

Thus, these two signs, gurgling sounds and sewer odors, are essential indicators that help in diagnosing whether the venting system is operating correctly during the drainage process.