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Gas prices are constantly rising, but heating with this type of fuel is still one of the most inexpensive. But we are talking about monthly expenses – modern boilers have a high efficiency – 95-98%, which reduces costs. A high degree of automation also adds popularity – you can leave the house for quite long periods without much risk (if the electricity is not turned off). That is why many people consider gas heating of a private house in the first place.
What can be gas heating
Two types of gas can be used for heating – main and liquefied. Main gas under a certain pressure is supplied through pipes to consumers. It is a single centralized system. Liquefied gas can be supplied in cylinders of different capacities, but usually in 50 liters. It is also poured into gas holders – special sealed containers for storing this type of fuel.
Cheaper heating – using mains gas (not counting the connection), the use of liquefied gas is only slightly cheaper than the use of liquid fuels. These are general statistics, but specifically it is necessary to count for each region – prices differ significantly.
Water heating
Traditionally, in private houses they make a water heating system. It consists of:
- a heat source – in this case – a gas boiler;
- heating radiators;
- pipes – connecting the boiler and radiators;
- coolant – water or non-freezing liquid that moves through the system, transferring heat from the boiler.
Scheme of water gas heating for a private house
This is the most general description of the water gas heating system of a private house, because there are still many additional elements that ensure operability and safety. But schematically, these are the main components. In these systems, heating boilers can be on natural or liquefied gas. Some models of floor boilers can work with these two types of fuel, and there are those that do not even require a burner replacement.
Air (convector) heating
In addition, liquefied gas can also be used as fuel for special convectors. In this case, the premises are heated with heated air, respectively, heating – air. Not so long ago, convectors appeared on the market that can operate on liquefied gas. They require reconfiguration, but can work on this type of fuel.
Gas convectors are good if you need to quickly raise the temperature in the room. They start heating the room immediately after turning on, but they also quickly stop heating – as soon as they turn off. Another disadvantage is that they dry the air and burn out oxygen. Therefore, good ventilation is required in the room, but there is no need to install radiators and build a pipeline. So this option has its advantages.
Types of gas boilers
According to the type of installation, two types of gas boilers are distinguished: floor and wall. Wall-mounted ones can only work with natural gas, floor-mounted ones can work with two types of blue fuel. The advantage of wall-mounted gas boilers is that they can be installed in kitchens – they are automated and safe. Some floor-standing ones can also be installed in the kitchen (up to 60 kW), but this room must meet certain requirements. Read more about how and where you can install gas boilers here.
Виды настенных котлов для отопления дома
First of all, it is worth dividing the gas heating equipment by functionality: it will be used only for heating or also for preparing hot water for technical needs. If water heating is expected, a double-circuit boiler is needed, only a single-circuit boiler works for heating.
Next, you should decide on the type of smoke extraction. There are gas boilers with atmospheric chimneys and open combustion chambers, there are turbocharged boilers (they have a closed combustion chamber). Atmospheric ones require a good chimney and draft in it, oxygen for combustion comes from the room in which the unit is installed, therefore there must be an air inflow channel and a working chimney (all this is checked when the system is started).
Boilers with forced draft (turbocharged) can be installed without a chimney. The smoke outlet of the boiler through a coaxial pipe (also called a pipe in a pipe) can be output directly to the wall. At the same time, smoke comes out through one pipe (it is pumped by a turbine), through the second, combustion air enters directly into the combustion chamber.
This type of equipment is good for everyone, except that in winter the coaxial is overgrown with frost, which worsens traction. In case of poor draft, the automation extinguishes the boiler – so that combustion products do not enter the room. Switching on is possible only when traction is restored, that is, you will have to upholster or remove snow growths in some other way.
There is also a separate type of boilers – condensing. They are distinguished by very high efficiency due to the fact that heat is taken from the flue gases (they condense vapors). But high efficiency is achieved only when operating in low-temperature mode – in the return pipeline, the coolant should not have a temperature above +40°C. If the temperature is even lower, even better.
Such conditions are suitable for heating with water heated floors. So if you have conceived such gas heating of a private house – with warm floors, then a condensing boiler is what you need. It has few disadvantages – a high price (compared to conventional ones) and caustic condensate, which places special demands on the quality of the chimney (made of good stainless steel).
Floor standing gas boilers
If you need more power, the wall-mounted option will not work – they have a maximum performance of 40-50 kW. In this case, put a floor boiler. Here they are of high power, and there are also models that can work in a cascade. In this way, large areas can be heated.
Some of the floor boilers can operate not only from main gas, but also from liquefied gas. Some can still work with liquid fuel. So these are pretty handy units. Their body is made of steel, and the heat exchanger can be steel or cast iron. Cast iron weigh and cost more, but have a longer service life – by 10-15 years. Inside the case there is a burner, automation and a heat exchanger.
When choosing, you need to pay attention to the functionality of automation. In addition to the standard set – control of the presence of gas, flame and thrust, there are many more useful functions:
- maintaining the set temperature,
- the ability to program modes by day or hour,
- compatibility with room thermostats;
- adjusting the operation of the boiler to the weather,
- summer mode – work for heating water without heating;
- the ability to work in parallel with solar panels or other alternative heat sources, etc.
The wider the functionality of the automation, the more expensive the boiler and its maintenance. But also many programs allow you to save fuel, which is no less important. In general, you choose.
Home gas heating schemes
We will talk about water heating using gas. Immediately it is worth deciding on the type of circulation of the coolant. It can be natural (such systems are also called gravity) or forced (with a mandatory pump).
Gravity systems require the installation of a large-diameter rub, that is, there is a lot of coolant in the system. The second point is that due to the fact that the coolant moves through the pipes at a low speed, the heating efficiency is not very high. Far radiators in long branches can be cold. It’s about disadvantages. There are many of them, but there is one big plus – systems with natural circulation do not depend on electricity. This is important in those regions in which the power is often turned off.
Now a little about systems with forced circulation. They are more efficient – the coolant moves at a given speed, delivering heat to all corners of the system. The presence of a pump allows the use of pipes of small diameters. This means that there is not much coolant in the system and it warms up quickly. In general, they provide a greater level of comfort, but have a serious disadvantage – they require electricity to work, that is, backup power is required. If the light is rarely turned off, it is enough to install an uninterruptible power supply unit with several batteries. They can ensure the operation of the boiler for tens of hours. If the light is turned off often and for a long time, you will also have to build a generator into the system. In any case, these are additional costs and considerable.
There are also combined systems – they are designed as gravity, but have a built-in circulation pump. Such a solution can be called ideal from the point of view of practicality: while there is light, the heating works as a forced one, as soon as the power supply is gone, everything works like a gravitational system. In general, a good option, except that the pipes will be large and too visible.
Wiring method
There are three types of systems – one-pipe, two-pipe and beam. In single-pipe radiators, they are connected in series to one pipe. This wiring method is economical – fewer pipes are required, but it is difficult to compensate – it is difficult to achieve the same heat transfer from radiators. The thing is that the coolant enters the first radiator in the hot branch – immediately from the boiler. It goes through it, cools down a little, hits the next one, cools down a little more. So throughout the thread.
It turns out that the coolant comes to the last radiator much colder than to the first one. The only way out is to take this phenomenon into account when designing the system and increase the number of sections in the radiator as you move away from the boiler. But the last radiators will still remain the coldest.
It is more or less easy to balance the system shown in the photo above. In it, on each radiator there are thermostats – devices that allow you to change the amount of coolant passing through the radiator. In order not to “crush” the circulation in the entire system, a bypass is placed under each radiator – a jumper through which the coolant flows, which did not go through the radiator.
In a two-pipe system, radiators are connected in parallel – to the supply and return pipelines. In this system, the consumption of pipes is much higher, since two threads are pulled at the same time. But in this case, a coolant with the same temperature is supplied to each heater, due to which the heat transfer of the radiators will be the same (if you put the same batteries).
In this scheme, you can also install thermostats, but this does not require bypasses – only the flow to one radiator is regulated. So despite the greater consumption of pipes, two-pipe systems are more popular.
The beam method of wiring is the most expensive in terms of the number of tubes. In them, to each radiator there is a separate supply and return pipe. It is connected to a collector – a device with one input and several outputs. In this case, adjustment is possible both on the collector and on the radiator using a thermostat.
Gas heating of a private house made according to this scheme will be the most reliable: if one of the pipelines is damaged, all the others will work. Therefore, this method is often chosen if the pipes are hidden in a screed.