Before contacting a company to install a stove within your home, it is best to understand a few basic tests your engineer should be carrying out and why.
There are three types of smoke test, all appropriate for different situations:-
- A Chimney Integrity Test – tests your chimney for damage.
- Appliance Air Leakage Test – test seals and doors for smoke leakage.
- Appliance Connected to Chimney Draw Test – checks made after installation of a stove.
The Chimney Integrity Test is used to check a chimney is sound and has integrity. You must carry out this test if you are not fitting a stainless steel liner. Even if a liner is being installed it is a test that you should consider having as it is better to know your chimney is safe with or without a liner.
If there are problems with your chimney that are not known, you could have insulation materials or smoke and gases released through your chimney into your home and/or into your neighbour’s home.
Two people should carry out the integrity check. The test involves sealing off the fireplace. The flue is warmed with a blow torch to start the draw. A large volume of smoke is added to the flue using one or more smoke pellets. When the smoke is seen exiting the pot at the top of the chimney the pot is then sealed. The smoke should remain trapped inside the chimney, when sealed, for at least five minutes.
Now the inside of the house, the chimney stack, loft and eaves of the house can be checked. If the chimney is on a neighbour’s wall, it is best to ask your neighbour for access to their home to check for signs of smoke.
Once the test is completed and the house has been given the all clear, the seal over the pot is removed to see if the smoke has been secured and trapped within the chimney (smoke billowing from the chimney is a good sign this has happened).
If smoke is detected outside of the chimney then repairs must be carried out before the stove is installed.
Note: Some people carry out a basic test and simply light a smoke pellet in the fireplace and wait to see if the smoke exits the pot, if it does, then they consider everything is fine with the chimney. This type of test should only be used when a gas appliance is being fitted and not a solid fuel burner.
Both of the following tests should be applied to a new stove before it is used.
The Appliance Air Leakage Test assumes that there is no extraction fan in a room. (Extraction fans can pull smoke out of a stove into a room and must be rendered inoperable for the period the stove will be installed). Your engineer should check this with you.
The stove should not be alight and the engineer should warm the flue with a blow torch or similar device for a few minutes. They should check the stove’s air inlet controls are closed before placing a smoke pellet inside the stove. The smoke needs to be watched for at least 30 seconds. All of the smoke should remain inside the stove. If however, smoke is escaping the stove, the rope seals and a general check around the stove is needed to find where it is coming from. Fire cement will need to be used to seal leaking joints.
The Appliance Connected to Chimney Draw Test literally tests the draw of the chimney and not its integrity.
Again this test assumes there is no extraction fan in the room.
The stove should not be alight, and all doors and windows in the room should be closed. A smoke pellet then is placed inside the stove and the doors closed, (or, left open if that is the usually way the stove is operated) the air inlet controls should be open. The smoke should be watched for at least 30 seconds. The smoke should remain within the stove and not enter the room.
A window should then be opened to see if the smoke speeds up or is drawn faster into the chimney. If it does speed up then there is not enough ventilation in the room. The appliance should be shut down until the correct sized ventilation is fitted.
The chimney also needs to be checked from the outside of the house, if the smoke is coming out of anywhere but the top of the chimney, the appliance will need to be shut down and investigated further.
We hope this helps you to understand why these checks are carried and why you should know what your engineer is doing.