How it Works
Flue Free contains very specific grades of montmorillinite and alkaline phosphates. Incorrect grades of material can actually build up deposits.

Flue Free is carried up the chimney by the flue gasses. the phosphates react with the acids in the creosote/tar and "fluidise" it. The montmorillinite soaks up these fluids producing a shrivelling or drying action, which weakens the bonding to the chimney surface. in many cases this causes lumps of creosote to fall off.

The phosphates also find their way onto the chimney surfaces and have the ability to afford some protection against corrosion. It is advisable to arrange for the chimney to be swept prior to commencing Flue Free treatment.

How long does it take to work ?
A difficult question to answer because of the variation in individual circumstances. Certainly results are quicker in insulated or small diameter flues. Under these circumstances, positive results can often be noticed after 2 weeks. In big old chimneys simply blanked off above the stove, the results can be much slower, particularly where the chimney is on the outside wall. Effectiveness also varies according to the degree of established deposits within the chimney.

Regular day dosing of Flue Free at normal dosage rates is much more effective than single shock doses. Single shock doses are only recommended in cases where normal dosage rates have proven insufficient.

Is the need for sweeping eliminated ?
Emphatically not but regular use of flue free will ensure that sweeping is likely to be much more effective because of the weakened bonding between creosote/tar and the chimney wall. The combination of Flue Free and reduced brushing frequency represents a good compromise in situations where very frequent wire brushing might reduce chimney life. In many circumstances the frequency of sweeping can be reduced but the need for sweeping is not eliminated.

It is important to distinguish between deposit conditions (like Flue Free) and combustion aids, whose main principal action is to cause creosote/tar to catch fire and burn off. Very often the materials are corrosive and some are toxic. The high temperature which can be generated by burning creosote/tar can also cause chimney damage.

What causes creosote/tar build up ?
The several resinous constituents found in all wood (wet and dry) cause the problem. As the wood is heated, creosote evolves as gas or liquid droplets and at low flue temperatures much will condensate. Sometimes it is fairly liquid, other times it is sticky and frequently it appears to bake onto the chimney surface.

Factors which affect flue temperatures are usage of wet wood, external or insulated chimneys, smouldering overnight fires, wood quality and low firing rates in relation to equipment capacity.

The main hazard associated with creosote is the danger of ignition - causing chimney fires. Flue Free will lessen the risk.

Directions for use

1. Remove excess ashes or cinders

2. Ensure damper and air vents are closed and fire is hot enough to burn the powder on contact.

3. Sprinkle 2 tablespoons of Flue Free onto a hot but low fire. (The effectiveness drops when applied to a high/roaring fire)

4. If no evidence of improvement is noticed after 2 weeks, increase dosage frequency.

5. In wood/solid fuel cookers/boilers, fires over 75,000 BTU or if chimney area is abnormally large, use double dosage.

6. For use in larger appliances, the following dosage rates can be used as a guideline:-

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