Smoking Stoves and Fires
A common problem with solid fuel fires and stoves is that smoke or smell gets into the room. There are two main causes of this problem.
1. Insufficient Ventilation.
If you have modern double glazed windows and tight fitting doors, there simply will not be enough fresh air coming into the room to feed the fire. You must have a free and constant air supply into the room.
Sometimes all that is needed is to have a small vent fitted into the door of the room this allows air to circulate. However, an under-floor air feed unit is the ideal solution for this purpose. Problem is that it is usually not a practical option as a retrofit, tearing up the floor of your living room etc.. If, on the other hand, you are building a new house or renovating extensively, and you intend to have solid fuel heating, it is very well worthwhile considering fitting an under floor draught supply.
This consists of two air inlet pipes underneath the floor. The pipes are generally of 10cm to 13cm diameter and must lead to two separate outside walls at right angles to each other. The two pipes come in and meet under the floor near the appliance in an air mixing box approximately 30 x 30 x 15 cm high. A third smaller pipe 75mm approx. diameter, leads to the area of the appliances air intake.
This system insures that warm air is not sucked out of the room to supply the fire, it also insures that there is a good and controlled air supply to the stove or fire.
The reason for this type of construct is to avoid a suction being created by a venturi effect, (wind blowing across a pipe will cause a suction), and it also avoids excessive air pressure when a strong wind is blowing directly into one of the pipes.
I will look at down-draught problems in the next post on this subject.