Smoke testing is by far and away the simplest way of testing flues for integrity. A smoke pellet is lit at the bottom of the flue, and allowed to rise up in the flue. The top of the flue is closed off, and if there are any holes in the flue, the smoke test allows smoke to pass out into an adjacent flue. Like the smoke from a fire, the smoke from the smoke test cools as it passes into the next flue and then falls down into the room served by that flue.
Disadvantages of a chimney smoke test
While a chimney smoke test is quick, cheap and easy, so are the results. Unfortunately, as the result of the test is reliant on the engineers senses i.e. how much smoke they can see or smell, the results are subjective and immeasurable. The biggest issue with this is that you cannot accurately measure the decline from one year to the next.
Alternatives to a chimney smoke test
A Flue Integrity Test is the same test as a chimney smoke test but it uses a machine that pumps air into the flue as opposed to smoke. This method has several benefits:
- It uses air as opposed to smoke so it doesn’t leave a smell in the home afterwards
- the results are objective and accurate
- the results are measurable
- it enables you to carry out the test at different points of time to track the speed of degradation