Municipalities have used smoke testing since the early sixties to diagnose sewer mains, laterals, pumping plants, public collection systems, and find sources of unwanted rainwater entry such as broken manholes. Today's plumbers can utilize that same methodology in a smaller version and incorporate those techniques in residential and commercial repair work. That's exactly what happened with inspection cameras. We took a diagnostic technique that was in the hands of the municipalities for years; made it smaller and cheaper and put it into the hands of plumbing companies. Let's borrow something else from the munis, shall we?
If you are in the business of pipe inspection and repair, smoke testing is a profitable addition to your diagnostic capabilities. The needed components are inexpensive and anyone can do it. A case of smoke bombs that costs you $60 can yield $5000 in testing charges. There's nothing hi-tech to worry about. If you can flip on a blower—you can smoke test.
Have you ever received calls from customers who complained of sewer odors wafting through their homes or businesses throughout the day? What service would you offer? How would you pinpoint the problem? There's only one way to do this job quickly and inexpensively—smoke the system. All that is needed is a smoke generating device (smoke bomb) and a way to push the special smoke into the system you want to inspect. I am astounded by how few plumbing and drain companies provide smoke testing. Pick up your local yellow page directory and try to find someone to smoke test your home—it's next to impossible. The market is wide-open for you to step in. Smoke testing will distinguish you from your competitors and create more sales opportunities. You can get started for under $100.
DIFFERENCES BETWEEN WATER AND SMOKE TESTS
WATER TESTING is left to new construction and remodeling projects where the pipes in question are exposed and traps have not been installed yet. The main drain must also be capped so the system holds water. Water testing drains and vents to find the source of escaping sewer gases in existing structures is not practical. The leak could be anywhere, including: in the drains; vents; failing traps; mechanical connectors; lose or missing cleanout plugs, a non-trapped fixture; outside; inside; under a slab, inside walls; attic spaces; etc. With a water test, the observer must be able to detect water drips visually.
SMOKE TESTING is used when the source of the leak is concealed or cannot be located by any electronic means. There is no limit to the possibilities of smoke testing. If you can fill it with smoke, you can test it. It can show you not only where water and gases exit a system, but also where unwanted inflow of rainwater enters a line, creating an extra burden on the system. Smoke testing shows you what a video inspection camera cannot see, can pinpoint what a locator cannot pinpoint and introduces your sense of smell into the testing process. In most cases the building drain does not need to be capped and that is a real time saving advantage over water testing. Another advantage is that smoke testing requires no plumbing work for set-up and allows you to test the total system under normal usage conditions. All traps are left in place so their water seal can be tested.
Restaurants are notorious for rotten traps under floor sinks and floor drains. One can easily identify failing trap primers. Smoke testing can be used to inspect HVAC systems, tanks and just about anyplace where water testing is not appropriate or a quick test is needed. On large municipal sewer installations, there may be an inspection provision that requires a smoke test immediately prior to back-fill. The smoke emits a strong identifying odor to assist in leak locations.