During the design of the greenhouse, the main task is to maintain the required microclimate. To solve it, it is necessary to provide maximum natural light, a good ventilation rate and heat supply. Indeed, the quality and volume of the future crop depends on which heating systems of the greenhouse they choose in winter.
Greenhouse heating requirements
It should be noted that before properly heating the greenhouse, it is necessary to choose the right material for its manufacture. It will affect the amount of heat loss, which will need to be compensated by heat supply. Only after a preliminary calculation of this parameter can you start choosing a heating system.
Since you can make your own heating in a greenhouse using various options - it is recommended to choose the most optimal one. One of the determining criteria is the type of energy carrier - gas, solid fuel, electricity.
Then it is necessary to analyze the technical characteristics of the building - its area, volume and heat loss. The future heat supply system should ensure uniform heating of the soil and air in it.
But besides this, it is necessary to highlight such requirements that heating of a polycarbonate greenhouse must meet:
- Humidity control. The functioning of the heat supply should not lead to a decrease in moisture. Abrupt changes in this indicator can lead to a deterioration in the quality of plant growth. The optimum moisture value should be at least 45%. But it depends on the type of plants;
- Warm air convection. The best result is achieved when water or air heating in greenhouses first heats the soil, and then the heat spreads upward;
- Plant safety. This applies to a possible temperature difference depending on the distance to the radiators. To avoid this, it is recommended to use the low-temperature mode of operation, which is characterized by infrared heating of greenhouses;
- High degree of autonomy and safety of heat supply. Even a small malfunction in the system can lead to a drop in temperature, especially in winter. Therefore, regardless of whether the greenhouse is heated with firewood, gas or with the help of electricity, the temperature control devices or mechanisms must be provided in the circuit.
These are the minimum heat supply requirements for greenhouses. A complete list can be found in the text of SNiP 2.10.04-85. It sets out the main factors affecting the microclimate, provides links to other regulatory documents.
The correct calculation of the heating of the greenhouse should include possible changes in the temperature regime depending on the type of plants. Therefore, it is recommended to pre-calculate several options for heat supply and choose the most suitable.
Types of heating greenhouses for placement
An important point is the choice of the location of the heating devices. In the future, this will affect the degree of soil heating and the overall temperature in the room. If heat-loving plants are grown, more attention is paid to heating the soil. To maintain normal air temperature, it is best to install a boiler for heating greenhouses with a water circuit.
It is currently possible to select one or more heating options.They differ in temperature conditions, equipment and maintenance requirements. But the determining parameter will be the microclimatic conditions in the room. Based on this requirement, you can consider three main options for heating greenhouses with gas, firewood or electricity:
- Volumetric. The main flow of thermal radiation is aimed at maintaining a comfortable level of air temperature. This method is an example for greenhouses with a minimum amount of natural soil - when growing flowers;
- Soil. In this case, the soil is heated. To do this, you need to know how to make water heating in a greenhouse with deepening the heat supply circuits. The optimal depth should be 25-30 cm. It is important that the roots of the plants do not suffer from excessive overheating;
- Vegetative. Its distinctive feature is the location of heat-conducting lines on the soil surface in the immediate vicinity of plants. In this case, furnace heating of greenhouses cannot be used, since the system must operate in low temperature mode.
Installation options for several types of heat supply are possible. They can be activated alternately or simultaneously. It all depends on the design temperature. So, for flowering, one of the best options would be infrared heating of greenhouses. For plants with a developed root system, they prefer to equip water heating.
Before installing heating, it is necessary to insulate not only the foundation of the greenhouse, but also the soil. This is necessary to reduce heat loss, which will inevitably increase in the winter.
Water heating in the greenhouse
The most common method of heating is the water heating of greenhouses with your own hands. For this, it is necessary to choose the right source of heating of the coolant (boiler), choose pipes, radiators, control and safety devices. The heat supply scheme in this case is largely similar to the brownie, but has a number of differences.
At the first stage, it is necessary to calculate the heating for the greenhouse, determine its optimal power and thermal distribution. The determining factor will be the type of heat supply for the placement of thermal appliances.
Using a traditional open pipeline will maintain air temperature, but will have a minimal effect on soil heating. In this case, the best option is to install highways under a layer of soil - an analog of a warm floor system.
Having decided on the type of piping, you can start choosing a boiler for water heating of greenhouses with your own hands.
There can be several options for organizing water heat supply:
- Solid fuel. It is characterized by minimal acquisition costs, ease of installation. However, in order to control the heating level, it is necessary to constantly add fuel to the boiler. An alternative is the installation of a boiler for heating greenhouses of long burning;
- Gas. In terms of ease of use is considered the best option. But based on existing realities, for heating greenhouses with gas, it is necessary to issue permits for connection to the central highway. In practice, this is associated with great difficulties. Therefore, most often the choice is stopped by balloon heating;
- Electric. One of the easiest ways to make do-it-yourself heating in a greenhouse. To install an electric boiler, you do not need to obtain a permit, you do not need to organize a separate place for storing fuel. But if the total power of the equipment exceeds 9 kW, a connection to the 380 V power line is necessary.
It is important to make the chimney system correctly. The ingress of carbon monoxide into the premises of the greenhouse is unacceptable. This can lead to the death of plants or their deterioration. This is often observed if there is steam heating in the greenhouse.One of the best ways to make water heating in a greenhouse correctly and safely is to install external and internal pipelines. Moreover, the diameter of the first should be from 32 to 40 mm, and internal - from 16 to 24. This will achieve uniform thermal distribution throughout the volume of the room.
In order for the water norm in the heating system of the greenhouse to be at a constant level, an automatic coolant adding system should be installed. To do this, just connect the return line to the water supply using the make-up unit.
Air heating in the greenhouse
For volume heating of air it is best to use air heating in greenhouses. This option is an example for regions with a mild climate in winter, as well as with the proper level of building insulation. There are several options for heating a polycarbonate greenhouse in this way.
The simplest of these is the use of heat guns. These are mobile units that can run on electricity, gas or diesel. Their advantage is not necessarily the arrangement of a complex piping system, some must be done for water heating in the greenhouse. The disadvantage is the high energy consumption. Therefore, this option is considered as an alternative if the main heating system fails.
Is it possible to independently make the correct heating of the greenhouse by air? To do this, you need to choose a source of thermal energy. It is possible to install several options for heating equipment:
- Factory air heating boiler. Its construction is similar to similar equipment for steam heating in a greenhouse. The difference is the lack of a water heat exchanger. Instead, the boiler has a system of circulating channels passing through the combustion chamber. They contribute to the rapid exchange of warm air;
- Homemade boiler. The advantage of this option of air heat supply in greenhouses is the ability to choose the optimal design of the heating device. An air heat exchanger is installed on top of the combustion chamber, which is connected to the duct system. They are located in the upper part of the greenhouse, and their output bells are directed downward.
For these options it is possible to use various types of energy carrier - heating the greenhouse with wood, using coal or gas. One of the disadvantages of this method is the likelihood of a temperature difference between the soil and the air in the room.
Before you make your own air heating in the greenhouse, you should consider the options for installing chimneys. In some sources, it is recommended to place the pipe under the ground for better heating. However, this will lead to a significant decrease in traction.
Electric greenhouse
It is often not possible to use traditional schemes for heating small polycarbonate greenhouses. This is due to the lack of space for installing equipment - a boiler, pipelines and radiators. Therefore, the only option left is the installation of infrared heating in greenhouses or an electric underfloor heating system.
This will require a good and reliable power line. Without fail, RCD, grounding and all required safety devices are installed. Only after these measures can you choose options for how to properly make the electric heating of the greenhouse. They are characterized by ease of installation and operation. Unlike gas supply to greenhouses, there is no need to equip a chimney system. But at the same time, one should not forget about ventilation - for the normal existence of plants, constant air exchange is necessary.
To organize infrared heat supply of greenhouses, wall or ceiling heaters are most often chosen.They provide heating of the soil surface. Heat is transferred from it to the air. This method is acceptable if no low temperatures are expected in winter. To optimize heating, you can optionally install an electric heating cable in the ground.
Thus, it is possible to provide comprehensive temperature control not only in terms of room volume, but also in soil. It is important that there are no problems typical for steam heat supply in the greenhouse - overheating of plants.
When designing electric heating in a greenhouse, you should pay attention to such factors:
- Mandatory installation of temperature controllers and temperature sensors. One of the advantages of the electric system over furnace heating of greenhouses is low inertia. But the thermal effect must be regulated automatically. For this, temperature sensors and temperature regulators are mounted;
- Possible blackout. In this case, you can install a backup power source - a diesel or gasoline generator. An alternative is to install an air boiler for heating greenhouses.
Once again, it is necessary to emphasize that this method of heat supply is an example for rooms with a small area and volume. Otherwise, the cost of energy (electricity) will negatively affect the cost and costs.
During installation of heating cable into the ground, before laying the main soil layer, sand 20–25 mm high should be poured. It is necessary to protect the root system of plants from possible overheating.
Greenhouse Recommendations
One of the easiest ways to heat a greenhouse with wood, coal or gas is to set up heat supply registers. These are large diameter pipes that are located around the perimeter in the lower part of the room.
This method can be used for greenhouses with a small area. If the external line is not enough - you can install pipelines between the rows of plants. But at the same time, it is necessary to ensure that the heat from the pipes does not damage the flowers. When installing batteries, an outdoor installation scheme is provided. This will contribute to additional heating of the soil in places of the highest heat loss - at the foundation of the greenhouse.
In addition to these factors, experts recommend the following actions when arranging water heating of greenhouses with their own hands:
- Lower piping preferred. But this takes into account the height of the greenhouse. Be sure to monitor the temperature in the room throughout the volume;
- Optimum temperature depending on the location of the highway. In case of soil installation, the heating of pipes should not exceed + 40 ° C. In the upper tier, this indicator may be equal to + 70 ° C;
- Installation of soil drainage. This is a mandatory measure when installing soil type heating. It is necessary to completely eliminate the possible effects of groundwater on pipes.
When developing a water heating scheme using a solid fuel or gas boiler, the location of the chimney should be correctly calculated. Carbon monoxide must not enter the ventilation system of the greenhouse. The minimum distance from the chimney outlet to the ventilation duct should be 4-5 m.
In the video you can see an example of furnace heating of a greenhouse:
