Commercial Sewer Smoke Testing in Phoenix

A smoke test makes an invisible path visible. We introduce smoke into the building's drain and vent network, and wherever the system is open to the building or the ground, smoke shows. That means cracked or broken pipe, open joints, missing cleanout caps, unsealed floor drains, openings where pipe passes through a wall or floor and vent connections that do not go where they should.

Public sewer agencies use the same technique at larger scale. EPA describes it as a way to find unwanted inflow from downspouts and yard or driveway drains and to identify cross connections between sanitary and storm sewers. For a business, that last use matters most. A roof drain or area drain tied into the sanitary line is illegal in Phoenix, which does not allow combined sanitary and storm drainage. Smoke testing is a standard way to catch it.

We use equipment that makes liquid smoke and forces air into the vent system, which fills the whole network evenly and stays visible long enough to trace. Some crews burn a smoke bomb and push the smoke with a shop vacuum. That can find a big leak, but the smoke is harder to control and a small leak can go unseen.

Here is the sequence:

1. 1Walk the building. Find the roof vents, the cleanouts and every floor drain, floor sink and trap.
2. 2Fill the traps. EPA says to fill every floor and sink drain with water first, so smoke shows leaks and not just empty traps. Dry traps are also a cause of sewer smell, so we note which ones were dry.
3. 3Notify people. Tenants and staff hear about it before it starts, because smoke inside a building can look like a fire to someone who does not expect it.
4. 4Introduce the smoke and watch. We watch the roof vents, the inside of the building and the exterior. We photograph and mark every point where smoke appears.
5. 5Report. You get the locations, what each one means and what the repair involves.

The International Plumbing Code describes a similar test for new work, with traps filled, thick smoke from smoke machines and the stack openings closed once smoke reaches the roof. That is a compliance test. Our work is diagnostic, aimed at finding a leak you can already smell.

• Smoke at a roof vent only. The vent system is open as it should be. No leak found in that run.
• Smoke inside a room. A path into the building: a dry trap, a failed seal or a cracked pipe in a wall or ceiling.
• Smoke at the ground outside. A leak in the lateral, a missing cap or an illegal connection. EPA cautions that the point where smoke surfaces is not always where it escapes underground, so a camera confirms it. See sewer smell outside a building near a cleanout or vent.
• Smoke from a downspout or yard drain. A storm connection that should not be tied to the sanitary line.
• No smoke anywhere. Good news for the vents and above-ground piping, but a buried crack may not send smoke anywhere you can see. The next tool is a camera. See smoke test versus camera inspection.

Smoke from a test can look alarming to people and, depending on the building, to detectors. Tell your alarm company and occupants before the day. HQ does not work on fire alarms or sprinkler systems, so that notice is the building's job. See whether smoke testing sets off fire alarms. Public sewer authorities notify police and fire dispatch, and tell residents to fill seldom-used drains.

If you have a stoppage, you need a cable or a jetter, not smoke. If the smell is only in one restroom, check the trap and the seal first. A smoke test shows its worth where the smell is general or intermittent, where there is a suspected illegal connection or where you need to find which tenant's drain is open. See when a smoke test is the right tool.

Call us with the address, what the smell does and when it happens. We can test before opening or after close. HQ offers 24/7 emergency service, free estimates and an upfront price before any work starts. The general page is smoke testing. If smoke points to a failed line, sewer repair and a camera inspection are the next steps. For the odor workflow, see commercial sewer odor diagnosis.