How to increase the heat output of the furnace
So, how to increase the efficiency of such a stove? There are several easy ways. The most elementary is to lay a brick screen around the stove. Bricks can not even be fastened together with clay, just put them on top of each other. You can fold such a screen near the side walls, or you can - at both side and rear walls. The brick will heat up during the burning of the fire, and when it becomes small or goes out, it will give off heat. You don't have to fill up fuel often. One of the features of the potbelly stove is that the stove is light and mobile. With such a screen, it will not lose its mobility, because the bricks can be dismantled at any time, rearrange the furnace and fold the screen in a new place.
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There is another way with a screen, which also increases heat transfer. In this case, a sheet metal shield is attached at some distance from the side and/or back wall of the stove. Sheets can be fixed with long bolts. In this case, the effect of convection is added.
There is another simple way to increase heat transfer. This time, the chimney of the potbelly stove is being modernized. Typically, these stoves have a straight chimney. It is taken out through the roof of the room in which the furnace is installed. If you add several elbows to the pipe, then the heat transfer will increase, however, not by much. In this case, the pipe will resemble the letter S.
If you want it to be much warmer, then you need to take 2 tanks from old-style washing machines. The tanks are welded together, and a chimney is passed through them. Thus, above the potbelly stove, which is heated by firewood, there is also a stove of the same size, heated by hot smoke. Heat transfer is almost doubled.
Another method is to weld additional ribs on the stove and chimney, for example, from metal squares. In this case, the chimney must be made of thick metal. Such ribs significantly increase the area of the heated surface. Increasing the area leads to faster heating of the surrounding air. The room is getting warmer. In addition, thick metal retains heat even when the fire in the furnace is no longer burning.
But still, it will not work to infinitely increase the efficiency of this heater. And if you want to have a full-fledged stove in the room, then you will have to fold it out of brick according to all the rules, so that the stove retains heat for a long time, for example, all night. For example, it is not required to increase the efficiency of the Russian stove; it retains heat for a very long time. True, in order to fold it correctly, you will have to call a stove specialist.
Furnace efficiency. What it is
The efficiency factor in relation to the stove is the ratio of the heat entering the room to the level of thermal energy that the fuel is capable of releasing. However, this indicator cannot be measured today for several reasons.
Firstly, at different stages of the furnace, the efficiency of the furnace will change.
Secondly, Efficiency varies depending on the fuel used, wet or dry logs.
Thirdly, this indicator is affected by heat losses: these can be flue gases, mechanical and chemical losses caused by incomplete combustion of the fuel. All this depends on how the furnace is arranged, what are the atmospheric pressure, temperature and humidity.
We will not be able to change many indicators, but there is still an opportunity to improve the operation of the furnace. Let's consider two ways.
Option two, allowing you to use the heat of the chimney
In the chimney, the air is heated to a very high temperature, since the brick warms up quite well during the combustion process. The longer the furnace is heated, the less heat the brick takes and the more the gases escaping through the pipe heat up. However, this also reduces the efficiency. To increase it, you need to use high temperature, which heats the gases that go through the chimney.
To increase efficiency, it is enough to build a steel pipe into the chimney. Both round and square tubes can be used for this. Their diameter can vary from two hundred to three hundred millimeters. When placing the pipe, care must be taken to slope towards the furnace.
Several pipes can be built into the chimney. It depends on the size of the oven. By arranging the chimney in this way, you will notice that the room heats up much faster, since the metal has a high thermal conductivity and allows you to transfer the heat of the chimney into the room, which used to go outside.
A well-heated pipe heats the air that circulates in the room, and at the same time does not create a vacuum, but rather enhances the movement of warm air. As a result, the room heats up faster, fuel is saved, and the efficiency of the stove increases significantly. However, such a reconstruction must be carried out at the masonry stage.
These two methods have already been tested in practice and proved to be effective. Connoisseurs recommend not being limited to one of them, but boldly introducing both in order to feel the difference both in fuel economy and in heating the house before use and after improving the stove.
What is a potbelly stove
For those who have never seen such stoves, you need to tell what a potbelly stove is. This is a firebox made of metal, with a straight chimney and a hole into which firewood is laid. These fireboxes are often made from any suitable metal object or welded from scrap metal. A potbelly stove can be round, for example, made from an old metal barrel, square or rectangular from iron boxes. The stove is placed on metal legs or just on bricks. The pipe exits through the roof. A potbelly stove is good because it is cheap, and you can heat it with any waste.
The operation of such a furnace is based on constant combustion. Thin metal quickly heats up and gives off heat to the room. Everything would be fine, but you just have to constantly keep the fire in the furnace, because when the flame becomes smaller, the stove begins to cool. It cools down quickly, and the room becomes cold again. But craftsmen have learned how to get out of the situation by upgrading the stove with their own hands. Having such a stove and upgrading it a little, you can get a very cheap heating device that will retain heat even after the fire goes out. And when burning, the converted potbelly stove will give much more heat than before.
