Wood-burning stove for the pool: characteristics, pros, cons, design options, step-by-step instructions, operation and maintenance

The most profitable fuel in terms of losses is fuel briquette and firewood, since storage losses are less and the ash content is low. Therefore, choosing a wood-burning stove for a pool will not seem like an unusual decision, given the low price of fuel and the fact that a huge amount of water will have to be heated. In addition, when burned, firewood does not produce such burning as coal or liquid heating oil.

Wood burning stove options for swimming pools

You need to choose a specific model according to 3 basic parameters:

1. A design that could be installed and connected with your own hands in a house or bathhouse without a major alteration of the room.
2. Furnace power. It should be enough with a margin of 30-40%. Unlike gas and briquette stoves, the heat output of the firebox largely depends on the quality of the firewood.
3. Duration of burning at one bookmark at minimum power.

With the last point, everything is clear. The body and design of the wood stove should be easy to carry so that you can bring it to the pool, set it up and use it as needed. For the winter or at the end of the season, put it in a utility room.

More difficult with the power of the furnace. First, you need to calculate the performance of the pool heater in terms of heat, taking into account the volume of water. Secondly, determine the dimensions of the furnace, taking into account a single load of firewood. Thirdly, choose a scheme.

Stove with a horizontal firebox

One of the most practical and convenient designs. In fact, this is a simplified version of a wood-fired sauna boiler. The furnace itself is assembled from two cylindrical bodies inserted into each other.

Inside the barrel there are cast-iron grates, on the facade there is a massive door on a suspension, like a locomotive firebox. A chimney is installed on the back side.

The heat is taken away by burning firewood with the help of a massive copper coil, bent from a thick-walled copper tube.

The scheme turned out to be quite successful, its power, when fully loaded with firewood, is enough to heat large pools up to 10 m3.

Similar furnaces for swimming pools can be found on sale. They are safe and easy to use.

You can lay a large charge of firewood, which is enough for several hours of slow burning and heating the water in the pool.

The only drawback of such a scheme is the increased complexity of manufacturing. It is quite difficult to build a stove with a horizontal firebox with your own hands correctly. But if you have experience and the appropriate equipment, then you can make a small wood-burning stove for the pool, by analogy with a sauna heater stove.

Read: Wood-burning stoves for summer cottages.

Wood-burning structures such as potbelly stove

In fact, this is the same sauna heater with a built-in heat exchanger. You can buy a ready-made potbelly stove, and not necessarily a classic cylindrical shape.

It will be more convenient to make a universal wood-burning heater. Use a ready-made steel or cast iron furnace as a base. You just need to weld a heat exchanger inside, and you get a stylish and reliable water heater for the pool.

Advantages of such ovens:

1. High heat output - up to 20 kW / h.
2. Fast ignition, the potbelly stove reaches the working mode of burning firewood in 10-15 minutes.
3. Closed design, no open flame, no sparks. Thanks to the chimney, the smoke quickly disappears, which greatly increases the convenience of using the pool.

In addition, the combustion chamber closed on all sides ensures relatively small heat losses, all the energy from burning wood is spent on heating water for the pool.

Of the shortcomings, only significant weight and a high center of gravity of the structure are noted. If the chimney is higher than 2.5 m (optimum height), the stove may fall with a strong shock or gust of wind.

Furnaces with open heat exchanger

They are used for heating water in relatively small pools. Most often, the design is a conventional coil made of steel or copper pipe, installed in a housing welded from stainless steel.

A wood burning stove with a built-in heat exchanger is often used to heat water in the field, they are mass-produced for heating greenhouses, greenhouses, even for car washes.

The firebox is usually vertical type, firewood is loaded from above. The water stove is relatively light (up to 12 kg) and easy to operate. The only problem may be the manufacture of the coil. It can be bought ready-made and is used to heat water in wood-fired sauna stoves.

Submersible furnaces

Unlike previous models, they are installed directly into the pool bowl filled with water. It is used mainly in the cold season at an air temperature of 4-12OWITH. Such stoves are also called winter. According to the owners, if you choose the right firewood, you can swim in the pool in winter.

Firewood is loaded into the firebox from above. This is best done from the side, so this type of furnace is used mainly for stationary pools with concrete walls and a hard bottom.

Homemade

In addition to proven designs, there are a large number of original home-made designs of stoves for heating the pool in the country.

For example, heating can be arranged using a conventional cast-iron radiator laid on a brazier from a gas cylinder. But loading firewood will not be very convenient. Such a furnace is interesting in that it is possible to assemble the structure in half an hour, and no scarce parts are required.

Instead of a cast-iron battery, you can use a car radiator or simply lay the coil on a stone stove made of crushed rubble. True, such stoves are not easy to maintain and often heat the water for the pool too slowly.

How to make a wood burning stove for the pool with your own hands?

The specific scheme of the furnace must be selected depending on the required heating power. In addition, it is necessary to select a suitable material for the heat exchanger, as well as perform calculations for the consumption of firewood. The power of the furnace directly depends on the volume of the firebox and the amount of firewood that fits.

Choice of materials and tools

If you need a large powerful furnace, then it is best to use stainless or low alloy steel for its manufacture. To make the case, you need welding, semi-automatic carbon dioxide or argon. To clean the metal, a nozzle with bronze bristles and a grinder will be used.

For the manufacture of the coil, you can use a metal pipe made of mild steel. The best option is to use a copper pipe with a diameter of 12-18 mm. It is used in air conditioners and refrigerators.

In addition, you will need:

• gas cylinder for 20-50 l;
• steel reinforcement 8-12 mm thick;
• ball valve;
• thermometer;
• water pump.

You will also need to prepare a small supply of firewood to test the stove until it is connected to the pool.

The choice of design scheme

The device of the furnace directly depends on the size of the pool. The larger the volume or area of ​​the mirror, the more heat is needed, and hence the firewood for the initial heating of water. Small stoves with a built-in coil are capable of delivering up to 4 kW / h of thermal energy. This is enough to maintain the temperature of the water in a small pool, such as a wooden tub or a frame-type tank.

For full-sized pools with a 3x4 m mirror, a small stove will not be enough. For heating, you will have to use not a coil, but a home-made long-burning water heater with double walls. The volume of the furnace must be calculated and checked for correctness of the calculation in practice.

How to calculate the power of the heater?

For the manufacture of the stove, it will be necessary to determine the volume of the furnace and the amount of firewood burned, provided that the pool needs to be heated in a maximum of one hour.

First of all, you need to calculate the volume of water. For example, we use a typical model with a diameter of 2 m and a depth of 1 m. In this case, the bowl holds V \u003d (3.14 * 22*1)/4= 3.14 m3 liquids.

In order to heat this amount of water, a certain amount of heat Q is required. To do this, you need to multiply the specific heat capacity of water (C \u003d 4.18 kJ / kg * K) by weight and temperature difference T2-T1. For example, a stove needs to heat water of 3140 kg per 10OWITH. For 3.14 m pool3 the amount of heat Q \u003d 4180 * 3140 * 10 \u003d 131252000 J or 131 MJ. If translated into a more familiar form, then 36 kW / h.

When burning 1 dm3 birch firewood produces heat of 2.6 kW / h. Accordingly, in 1 hour you need to burn 14 dm3 birch. After that, the stove can heat water only by maintaining the water temperature at the right level. That is, in order to heat water with firewood, it is necessary to ensure an influx of heat at the level of 10 kW / h for each cubic meter of pool volume.

If we take into account heat losses at the level of 20%, then a firebox with a volume of at least 20 liters is required to heat water with a stove. At the same time, the degree of filling of the firebox with firewood must be at least 90%. The diameter of the heat exchanger pipe is 15-18 mm.

It is best to make a pool stove from an old gas cylinder.

Read: Do-it-yourself oven masonry.

Step by step instructions for making

When calculating the characteristics of the furnace and the dimensions of the furnace, several important parameters of the future water heater were not taken into account at once:

• wall material;
• level of losses during water heating;
• the speed of the water flow through the heat exchanger tube.

It is quite difficult to calculate their influence on the efficiency of water heating in the furnace. You can adjust the degree of water heating using an electric pump. By changing the performance of the pump and the flow of water through the pipe, you can make the flow hotter or cooler.

Heat exchanger manufacturing

It is best to use a copper pipe with a diameter of 18 mm and a wall thickness of 1.5 mm for the furnace. You will need a blank with a length of at least 20 m. To make a coil, you need:

• fill the pipe with dry sifted sand;
• hammer holes at both ends;
• place a wooden blank with a diameter of 20 cm in a vise;
• make a loop, fix it and wrap the pipe around the workpiece.

For normal operation of the furnace, at least 15 turns are required. The pipe is annealed, after which the plugs are removed and the sand is removed. The outer surface of the copper must be cleaned with fine sandpaper and blackened with an etching solution.

Checking the health of the heating circuit

Before assembling the stove, you need to check the efficiency of its work on wood. The calculation of water heating in the pool was carried out without taking into account the material and thermal conductivity of the heat exchanger walls. Therefore, it is necessary to make sure that the firebox, with a standard laying of firewood, is capable of heating water to a temperature of at least 50OWITH.

To do this, we assemble a temporary building, you can take any metal box, lay the grate from the reinforcement on the bottom and put the coil. Next, you need to connect the hoses, the pump, lay the firewood inside. We light the logs and turn on the water supply. After the firewood flares up, you need to measure the temperature of the water. If the thermometer showed the required temperature, then a permanent housing can be made.

In addition, you need to adjust the water flow through the heat exchanger. In order for the heat from burning wood to be fully used, it is required that the flow through the furnace coil be at least 1-1.3 l / s. If the flow rate is less than 0.5 l / s, then the water in the furnace may boil.

Production of the furnace body

You will need a whole, maybe not new, but most importantly, not a rusty gas cylinder. All that needs to be done is to cut out the bottom and the lid with the valve.

The next step is cleaning the surface from rust and paint to “white” metal. This must be done, otherwise the paint will burn during the burning of firewood. To prevent the metal from rusting, you can treat it with phosphoric acid and let it stand for a day in a cool place. Then wipe with a damp cloth and dry.

Next, you need to weld the coil and install the legs, they are also made of reinforcement. After assembly, you need to make a control bookmark of firewood in order to determine the actual amount of fuel that is placed in the firebox.

It remains to tile the area in front of the pool, lay and connect the hoses, the pump and make the first start.

Advice! The stove will heat the water for the pool on any wood, but you can use an extension chimney to speed up the ignition process.

Due to the increase in traction, firewood flares up faster. But then it is better to remove the chimney, since a large amount of heat escapes due to the pipe.

Operation and maintenance of a wood burning pool heating system

Best of all, the firebox will work on birch, oak firewood, acacia, ash logs. Firewood from poplar, pine or spruce will definitely not work. The first gives too little heat to heat the pool, conifers emit a large amount of resin. It is enough to heat the stove once with pine chocks so that a thick layer of tar and soot appears on the heat exchanger.

How the stove is usually used:

1. Before ignition, small chips with paper are placed in the firebox, lit and allowed to burn out at least half.
2. Larger logs are laid, the water supply is turned on, and a chimney is mounted on top.
3. In an hour, it will be necessary to knock out part of the ash through the grate and lay a new portion of firewood. Instead of a chimney, the upper section of the furnace is covered with a steel sheet, leaving only a small gap.

Firewood will slowly smolder, and not burn, the heating power will decrease by about half. The hoses from the pool to the pump will need to be looped, the firebox will heat the water to the desired temperature. In this mode, the stove can work up to 2.5 hours, until all the firewood in the firebox burns out.

The pump must run constantly while the wood is burning in the stove. If you need to urgently stop heating, then the firebox is simply filled with a small amount of water.

Results

A wood-fired pool stove is considered one of the easiest and most economical heating options. The construction of the furnace will be inexpensive, the main costs are associated with the manufacture of the coil. In addition, the system will turn out to be safe, since volatile or liquid fuels are not used for combustion.

Tell us about your experience in making swimming pool heaters. What designs do you think are best for a home pool? Also save the article to bookmarks and share it on social networks.