5 Common Chimney Flue Problems to Avoid

What is a Chimney Flue?

The chamber where smoke and other combusted byproducts are vented is called the chimney flue. The flue is surrounded by the chimney and works to give insulation from heat, reducing the risk of fire. One chimney can have multiple flue if the home has several stoves or fireplaces. Chimney flues need routine maintenance to avoid getting chimney flue problems.

1. Vertical Cracks in the Chimney Flue

When the flue lining expands, it can cause vertical cracks in the structure of the chimney. Especially when the flue is hidden within the thickness of a wall. This is the point of weakness that causes failure. This problem can be fixed by installing a flue liner. The flue liner provides thermal insulation and heal the crack.

2. Dampness

Problems come from the damp however it enters the flue. The humidity combines with sulphates and accumulates inside of the flue because of combustion that form weak acids. The acids destroy lime in the parging, the mortar joints, and the brickwork. A ventilated flue the warm air will rise consistently. It is essential to support flue ventilation to avoid moisture levels increasing in the chimney. To fix this problem, line the flue and strip the plaster away from the wall. This allows the wall to dry out. If there is moderate staining, it can be plastered again after it is dried out. If the staining is severe, new finishes need to be applied.

3. Condensation

Moisture that condenses can causes a problem in flues. When fuel is burned, it produces water vapor. If the flue is cold, the gasses may be frigged enough to cause the vapor to condense into the flue. This especially happens when wet fuel is used. To reduce condensation, add a flue liner.

4. Rain

You can prevent rain from coming down the flue by using a restrained capping. There are caps available for flues that are no longer in use except for ventilation. If the flues are in use, the vessels may be affected by the capping. This will cause the fire to smoke. Experts recommend applying a sheet of lead all the way through the anatomy of the chimney right above the roof-line. Also, experts suggest creating higher flashing.

5. Using Too Much Fuel

If your flue is large and not insulated well, it will need a lot of heat and fuel to draw. Modern and high-efficiency appliances have a small outlet pipe for fumes. If the fumes are released into a larger flue, the rise can be slowed down not allowing the appliance to draw. The correct size flue will make sure an acceptable daught is made to burn as their designers wanted. The height of the fireplace opening is critical.