DIY heating with natural circulation

It’s not necessary to rely only on pricey heating systems to keep your house warm in the winter. DIY heating with natural circulation is an economical, eco-friendly method of heating your home. This technique lowers your energy costs while maintaining comfort levels by utilizing the power of natural air movement to distribute warmth throughout your living spaces.

Natural circulation relies on the idea that hot air rises and cold air sinks, in contrast to conventional heating systems that need pumps or fans to move warm air. A natural airflow that transfers heat from the source of generation to the areas most in need of it can be created by placing heating sources and vents in strategic locations. This strategy reduces the environmental impact of traditional heating methods while simultaneously saving money.

Taking an active role in the heating of your home is what it means to embrace DIY heating with natural circulation. It is your choice to create and implement a system that complements your environment and way of life. Whether you’re building a new home or remodeling an old one, adding natural circulation heating can be a satisfying project that benefits your family’s comfort and finances.

Topic DIY Heating with Natural Circulation
Description A guide to setting up a heating system that uses natural circulation without pumps or electricity.

Heating schemes with natural circulation in a private house

How does the diagram work with natural circulation

Commonly used as a coolant, ordinary water follows the curves from the boiler to the batteries and back because of variations in their thermodynamic characteristics. In other words, heat causes the fluid’s density to drop and its volume to rise, forcing out the cold stream that rises through the pipes. The coolant’s temperature drops as it diverges on horizontal branches and returns to the boiler. So, the circle is now complete.

If a private home was to have heating with natural circulation, all horizontal pipes would be installed with a slope toward the coolant’s direction of flow. This prevents the radiators from "gettingold." Because it travels up the pipes, into the expansion capacity, and finally into the air, the air is lighter than the liquid.

As the temperature rises, a liquid that has a higher volume merges into the tank, producing constant pressure.

What depends on the pressure?

When designing a private home, you must unquestionably account for the entire heating system in order to generate the required circulation pressure. It is dependent upon the lowest battery and the boiler’s midpoint level. The better the liquid flows through the system, the greater the height drop. The difference in the densities of the cooled and heated fluids affects it.

The heating system is characterized by a natural circulation caused by temperature changes in the boiler and radiators that happen along the central axis of the devices. Warm water comes from below and is at the top. The chilled liquid travels down the pipes due to gravity.

Movement is directly correlated with radiator installation height. Its increase is facilitated by the slope of the return line going to the boiler and the angle of inclination of the feed line facing the batteries. This makes it possible for liquid to more easily overcome the pipes’ local resistance.

In a private home with natural ventilation, the boiler is positioned lowest to raise all of the batteries when installing a heating system.

Heating systems schemes

The heating system’s design is dependent upon multiple factors:

  • Battery connection method with feeding risers. There are single -pipe and two -pipe systems;
  • place of laying the line that supplies hot water. It is necessary to choose between the upper and lower wiring;
  • Line laying schemes: a deadlock system or passing water in the tracks;
  • risers can be located horizontally or vertically.

What distinguishes forced circulation from natural circulation?

The forced movement of the coolant indicates that liquid is flowing through the roadway as a result of the pump’s laborious effort. The coolant in this natural system moves because of the difference in weight between the heated and cooled liquid, requiring no additional equipment.

One -pipe scheme: how to adjust the temperature?

There is only one wiring option available for a single-pipe heating system with natural circulation, and that is the upper. Since the liquid cooled by radiators returns to the supply line, it does not have a reverse riser. The water in the upper and lower batteries has a temperature differential thanks to the coolant’s movement.

The heating devices on the lower floor should have a slightly larger surface area than those on the upper floors in order to maintain a consistent temperature in rooms situated at different levels. The lower radiators are filled with a heated and cooled fluid from the upper heating devices.

In a single-pipe system, the fluid can be in one of two versions: in the first, it goes to the battery, and in the second, it goes further along the riser to the lower radiators.

In the second scenario, the coolant flows through every component beginning with the upper. One unique feature of this wiring is that the batteries are only connected to the lower floors’ chilled coolant.

Additionally, if the first version allows you to use cranes to change the temperature in the rooms, the second version prohibits this use because it will lower the coolant supply to all batteries that come after. Furthermore, the system’s fluid circulation will stop when the crane fully overlaps.

It is preferable to install a single-pipe system with wiring that allows the water supply to each battery to be adjusted. This will allow the temperature to be adjusted in different rooms, increasing the heating system’s flexibility and efficacy.

A single-pipe system can only be installed in buildings with an attic since it can only be the upper. A supply pipeline ought to exist. The primary drawback is that heating can only be turned on right away for the entire house. The system’s primary benefits are its reduced cost and ease of installation.

Pros and cons of natural circulation

Benefits of the natural fluid circulation heating system:

  • lack of difficulties in installing, starting and using;
  • The resistance of the heat of the system. Based on the gravitational movement of the liquid, it gives the greatest thermal return and maintains a microclimate in the rooms at the right level;
  • economy (with good insulation of a private house);
  • Work without noise. There is no pump – there is no vibration and hum;
  • Independence from power outages with electricity. Of course, if the installed boiler can function without electric current;
  • A long period of use. With a timely technical service without overhaul, the heating system can operate for more than thirty -five years.

The primary disadvantage of natural circulation heating systems is their limited coverage area and action radius. Place it in private residences that don’t have more than 100 square meters. The heating system’s horizontal radius is restricted to 30 meters because of the low circulation pressure. One essential need for any home is an attic big enough to accommodate an expansion tank.

The house warms up slowly, which is the biggest drawback. Pipes passing through unheated rooms in a system with natural movement must be insulated to prevent fluid from freezing.

Generally speaking, some materials require such a system; however, if the pipeline’s local resistance needs to be decreased, using larger pipes will increase costs.

An essential prerequisite for pipe laying is:

  • a system with the smallest number of turns that will interfere with the fluid flow;
  • harsh adherence to the recommended angle of inclination;
  • The use of pipes with a design diameter.

Installing a heating system necessitates closely adhering to technical specifications. A decrease in fluid circulation is threatened by noncompliance with the regulations. It will not be able to guarantee that the coolant moves along the line if there are rough mistakes in the system’s arrangement.

We calculate the one -pipe heating system ourselves

The primary steps in determining water heating are:

  • calculation of the desired power of the boiler;
  • the calculation of the power of all heating devices that will be connected to the system;
  • Selection of pipes size.

The computation of the boiler’s power

Heat loss through the house’s walls, ceiling, and floors is taken into account when calculating the boiler’s capacity. When calculating power, the area of surfaces, the manufacturing material, and the temperature differential between the interior and exterior of the house during heating must all be considered.

Determination of the battery power and pipe diameter

The following formula can be used to determine the pipes’ required diameter:

  • Determine the circulation pressure, which depends on the height and length of the pipes, as well as the difference in fluid temperature at the output of the boiler;
  • Count pressure losses in direct areas, turns and in each heating device.

Such computations can be completed by anyone without specialized knowledge, but it is highly challenging to calculate the whole heating scheme using natural circulation. Huge heat losses will result from even a tiny mistake. It is therefore best to leave the calculations and the subsequent heating system installation to the experts.

  • Author: Vadim Nikolaevich Lozinsky

Are you trying to heat your house without having to deal with complicated pumps and systems? Your solution might be natural circulation heating done at home. This method uses the basic laws of physics—that hot air rises and cold air sinks—to maintain a comfortable home. You can achieve a comfortable temperature without spending a lot of money on energy by carefully positioning heating sources at lower points and letting warm air naturally circulate upwards. Additionally, adding a touch of rustic charm to your space can be achieved by using natural materials for your heating elements, such as clay or stone. Accepting natural circulation not only saves you money but also provides your house with an environmentally friendly, sustainable heating solution.

Heating system with natural circulation: 2 methods of installation of pipelines

Regardless of the type of boiler being used, the pipes and radiators installed in the home must be properly arranged to allow for the proper circulation of coolant for efficient heating of a house or apartment. The gravitational system is the most popular and efficient. We’ll talk about the fundamentals of how it functions, the different types that are currently available, and how to build natural circulation heating with your hands below.

For tiny homes and cottages, a summary heating system is an excellent choice.

Principle of operation

For the purpose of arranging engineering heating networks, there are two primary schemes:

  1. Heating system with forced circulation. In this case, pumping equipment is used, thanks to which the water current is provided in the right direction. The disadvantages of such a solution are the noise produced by electrical devices, as well as the dependence of heating on the availability of electric energy.
  2. House heating with natural circulation. In this case, the water current from the boiler to heating radiators is ensured by a change in the thermodynamic characteristics of the liquid.

Essentially, this is how it works: when water is heated, it expands and its density drops, pushing the liquid upward into the upper portion of the heating system. The cycle continues as the coolant gradually returns to the boiler through the pipes.

The gravity heating system’s schematic is shown in the picture.

Take note! The only conditions that allow for natural heating circulation are correctly installed pipes and an expansion tank. The latter is required to establish the proper pressure in the engineering network and remove air from heating radiators.

One of the scheme’s drawbacks is that the water heating system with natural circulation has a lot of inrimentality and isn’t very good at heating large rooms (100 kV meters and up) or homes with five or more rooms.

Circulation pressure

The heating system with natural circulation must be accurately calculated in order for the heat transfer facilitated by the coolant to be as efficient as possible.

In the meantime, it’s critical to consider the following indicators:

  • The difference in heights between the location of the boiler heat exchanger and the drain hole of the lowest heating radiator – the larger this value, the better the liquid will circulate;
  • the temperature to which the water is heated in the chamber of the gas, electric or solid fuel boiler – the greater the difference, the more efficient the system will work;
  • The height of the installation of radiators and the angle of inclination of pipelines – the higher this indicator, the more effective the cooled coolant will overcome the internal resistance at the reverse current to the boiler.

An experienced engineer or architect should perform the system’s calculations.

Note: If the heating boiler is placed above the heating radiators, the heat exchanger will not receive cold water. Because there is nowhere to install a heater, individual heating via natural circulation is not utilized in urban apartments.

The power of the boiler, the central component that heats the coolant supplied to the heating radiators, must also be precisely calculated when building any heating system.

For this, the formula that follows is applied:

Where: W = WUD * S / 10

  • W is the desired capacity of the equipment, kW;
  • WUD – coefficient of amendment to a geographical area (from 0.7 to 1.5 depending on the climatic zone);
  • S – area of heated premises, sq.m.

Methods for constructing pipelines

Two very distinct schemes can be used to install natural circulation heating in a private home.

The characteristics listed below set them apart:

  • The method of joining water heating radiators with trunk pipes. The water supply – there is a single -pipe and two -pipe scheme (the price of the last option is higher due to the increased consumption of materials, however, it is more effective);
  • the place of laying of the main water pipelines – they can be located at the top (above the radiators) or below (along the floor);
  • The arrangement of water pipes – dead ends (water is supplied to each radiator separately and is removed from it in the same way) or a significant one, when the coolant, flowing from the upper to the lower point, passes all heating radiators;
  • the location of the risers – they can be fixed horizontally and vertically.

There are numerous considerations that must be made when selecting a heating installation plan.

Method 1. One -pipe gravitational heating system

Only the upper wiring of the main channels can be used for natural heating, which is made in accordance with the plan using a single pipe. Here, as the name suggests, a feeding line is set up where the liquid is returned after passing through radiators that heat it.

In this instance, the difference in temperature and, consequently, density, organizes the natural fluid current.

If the gravitational heating system is installed in a two- or three-story building, the area occupied by the heating radiators must be decreased as the number of stories rises. In this instance, uniform heating will occur even though the coolant’s temperature drops.

  • Parallel – part of the water enters the radiator, and the rest of the coolant through the main channel passes further (the advantage of such a solution is that with the help of manual or automatic shut -off valves, the volume of hot water supplied to the heating panel can be limited, and thereby reduce the temperature in room);

The house’s parallel heating system

  • Castle – in this case, the entire volume of heated water flows through each heating panel in the house (you will not be able to adjust the volume of the water supplied into the radiator, and also completely overlap it, as this will lead to impaired operability of the entire system).

The cottage’s propane heating system

Counseling! One can think of more than one parallel scheme. It allows the temperature regime to be changed independently in every room. Consequently, the energy carrier (diesel fuel, gas, etc.) reaches its full potential and the room’s microclimate becomes more comfortable.

Because only one channel can be used for the water supply in a single-pipe system, this type of heating arrangement is only feasible in buildings with attic floors, where boiler-heated pipes are located.

The inability to launch the system partially is one of the drawbacks of a single-pipe scheme. On the plus side, installation work and material costs are reduced, and the scheme looks good.

Method 2. Two -pipe gravy heating network

In this instance, two pipelines must be installed:

  1. Incoming. He delivers warmed coolant to the batteries. A pipe stretches from the boiler, which enters the expansion tank necessary to create pressure in the highway. From him, waterways go to heating radiators.
    The volume of the expansion tank used depends on the size of the heating system. In some cases, this device should be equipped with an overflow pipe that removes the remaining fluid.
  2. Output. According to this pipeline, the cooled water is transported to the heat exchanger of the boiler for heating. The cold line should be laid in the same rooms where the supply channel was mounted.
    This is a more effective scheme, as it makes it possible to better control the temperature regime in the rooms. Its disadvantages are the high cost of installation and bulky.

A heating system with two pipes.

The choice of the design of the riser

There are primarily two choices:

  1. Vertical riser. In this case, all pipes from heating radiators are joined with a central element passing through each floor of the house. The advantages of its use include the lack of risk of the formation of air traffic jams, the minuses are high cost (more pipes connecting the central pipe with radiators are necessary).

Heating plan featuring vertical escalators

  1. Horizontal riser. All heating panels on each floor are connected to one feeding line. A more economical option. However, in this case, it is necessary to additionally install special air valves that will prevent the “fanning” of the heating network, which affects its effectiveness.

Circuit for heating with horizontal risers

Advantages and disadvantages

There are numerous benefits to using a heating system that allows the coolant to circulate naturally, the primary ones being:

  • simple installation, commissioning and maintenance;
  • The maximum efficiency – the gravitational heating network has a high efficiency and makes it possible to adjust the temperature regime of each room separately;
  • Economics – a gravity heating network is one of the least costly among existing house heating systems (if you take measures to reduce the thermal conductivity of walls, floor and roof);
  • noiselessness – the lack of working electrical equipment minimizes the noise accompanying the operation of the climatic system;
  • Energy dependence – the gravitational heating network launched into operation will also work in the case of temporary termination of electricity supply, which would be different to power pumps;
  • A long service life – with proper installation and proper maintenance, heating equipment will work for more than 35 years without the need for capital reconstruction.

A gravity heating system ensures warmth and comfort within the home.

The primary drawback of natural circulation heating is that it cannot be used in large buildings. The length of the horizontal pipeline sections shouldn’t exceed 30-35 meters due to the liquid’s low pressure; otherwise, the system’s efficiency will significantly decline.

Furthermore, the upper portion of the building, where the expansion capacity is mounted, must have a technical floor.

Additionally, because of the low inertiality of the material, it is advised against installing pipes in unheated rooms as there is a chance that the coolant may freeze and compromise the pipelines’ integrity.

A system with natural circulation is possibly the greatest option for a small country house’s heating configuration. It is, however, completely inappropriate for a summer home, a city apartment, or a cottage larger than 100 square meters, where year-round habitation is not anticipated. In this situation, it is preferable to focus on alternative heating techniques, which are covered in the video below.

Heating system with natural circulation

Even though modern building technologies are widely used for heating purposes, natural circulation heating systems continue to be highly popular. The popularity of such an autonomous heating system becomes evident when we consider the instability of the private sector’s electricity supply, which is mainly to blame. It is also easy to install.

How it works

Scheme for gravitational heating

It is important to note that the system functions without forcing the coolant to circulate because of a unique device. The reason for the water movement in the pipes is that as the water cools, its density rises. This water flows to the boiler through pipes buried beneath the slope, pushing out the heated water.

Even though a pump is not necessary for the natural circulation heating system to function, it is still preferable to install one. The room warms up more quickly when the pump is turned on because the coolant moves through the pipes more quickly.

Water exits the boiler through the accelerated collector, travels to the top, and then cools as it passes through pipes positioned beneath the boiler’s incline.

Disadvantages and advantages

We must wait a long time.

Let’s discuss the shortcomings first. Using this method will assist you in determining if a heating system of that kind is right for you.

  • If the system does not have a pump, then you need to wait quite a long time until the hot water reaches the batteries and passes along them.
  • Uneven heating of heating radiators. This is due to the same nuance – hot water on top, and cold from below.
  • Installation is performed by more expensive pipes of large diameter.
  • It is necessary to install an open expansion tank, as a result of which the water evaporates and it should be periodically added to the system. Installation of an expansion tank of a closed type can worsen the operation of the system.
  • The design of the room suffers.
  • You can not break the bias of the pipes, even if you need to get around the doors.
  • The system should have as few turns as possible.
  • When planning a heating system without a pump, it is necessary to correctly determine the level of location of the batteries, an expansion tank and a boiler, which should be installed at the lowest point.


  • Electronics dependence. Even if the pump is installed, then when the electricity is turned off (or when the pump fails), the heating system continues to work.
  • Installation and further maintenance does not require special skills.
  • Surriety of work.

Types of systems

As was previously mentioned, the heating system’s gravity system cannot function if there are any variations in height. Consequently, multiple contours can be created.

Single -circuit

Diagram of connections with natural circulation

Here, everything is very obvious: batteries are connected between the two pipes that come from and go to the boiler. The plan that is being presented will assist in solving it.

A single pipe can function as a single circuit. The fact that each battery in the gravity system after this one will be noticeably colder than the last must only be considered in this specific situation.

Double -circuit

The coolant flow in double-circuit systems can vary in direction:

  1. With oncoming traffic.
  2. With a passing movement.

The location of the door in the room and other factors that make it impossible to install a return in this location determine the best mounting technique for the pipes while taking the coolant’s direction of movement into consideration.

The pipe slope angle remains constant regardless of the chosen system.

It’s not always necessary to have sophisticated systems or costly equipment for home heating. Using the power of natural convection, natural circulation heating provides a straightforward and affordable way to heat your room evenly. With just a few basic components and an understanding of heat transfer and airflow principles, you can build an efficient heating system.

The simplicity of natural circulation heating is one of its main benefits. These systems are frequently simpler to install and maintain because they don’t require any pumps or electrical components. They are therefore a great choice for do-it-yourselfers who want to lower their energy costs without sacrificing comfort. Furthermore, because natural circulation systems frequently use less energy to run than conventional forced-air systems, they can be more environmentally friendly.

For a natural circulation heating system to operate as best it can, careful planning and design are essential. The arrangement of your rooms, insulation, and heat sources can all have a big impact on how effective and efficient your system is. You can customize your heating solution to deliver dependable and constant warmth during the winter months by taking the time to evaluate the unique requirements and features of your house.

In conclusion, natural circulation combined with do-it-yourself heating provides a cost-effective and environmentally friendly way to heat your house in the winter. You can design an eco-friendly and efficient heating system by taking advantage of convection’s natural forces. You can have a warm and inviting home without going over budget if you plan ahead and pay close attention to details. Thus, why not investigate the potential of natural circulation heating and initiate the process of creating a cozier and more welcoming living area?

Video on the topic

Water heating from the furnace. Installation of heat exchanger. System test and natural circulation.

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