The modern market provides a huge selection of various equipment for greenhouses. Among them: automatic watering, humidity control, independent heating and much more. Plant care is, without a doubt, very important. But to achieve the desired effect without proper ventilation is very difficult.
In order to maintain an optimal climate in a greenhouse or greenhouse, it is necessary to ensure air circulation. This process can be automated by installing automatic machines for ventilating greenhouses.
Modern ventilation systems
Of course, you can ventilate the greenhouse in the old proven way - manually, but still the installation of automatic systems is considered a more convenient option. Modern systems can be divided into the following categories:
- Automated volatile.
- Automated non-volatile.
The former operate, as a rule, from a power source (for example, a power supply). Some of them use alternative energy sources (solar panels, wind generators, etc.). The basis of such devices are thermal relays. This mechanism drives electric fans. The latter, in turn, supply fresh air to the greenhouse.
The advantages of such automation for greenhouses include the following advantages:
- compatibility with designs of any sizes;
- compactness of the device;
- ventilation is carried out only at a certain time or according to the readings of the sensors.
It is important to note that all volatile designs are high-tech.
The following disadvantages of such systems are distinguished:
- difficulty in repair (in case of failure of just one component, you have to repair the whole mechanism);
- if the power supply is turned off, the machine will not work, due to which plants can die.
To choose the right ventilation system, you should pay attention to:
- The size of the greenhouse and its design.
- The number and area of window leaves. If it is not possible to install one large one (which occupies 1/5 of the entire roof area), several small ones should be opened at once.
- The load capacity of the device, which must correspond to the weight of the window.
Standalone ventilation systems
Stand-alone ventilation systems for greenhouses include:
- Bimetallic. Such a device consists of two metal strips, which, in turn, have different coefficients of thermal expansion. They overlap and connect at the ends. When the temperature rises, one of the bands changes position - it bends. Sufficient area of an unstable plate creates a lot of force, and the window opens. If you add a piston device to this design, you can build a stand-alone device that will work without a power source. When the temperature drops, the plate cools and returns to its original position. Accordingly, the window is closed.
- Hydraulic.
- Pneumatic
Advantages and disadvantages of autonomous systems
The advantages of bimetal greenhouse ventilation machines are:
- affordability in a price category;
- no need to connect to a power source.
The main disadvantages are:
- low power;
- difficulty in selecting the optimal temperature for the proper functioning of the machine.
Hydraulic Greenhouse Ventilators
The hydraulic automatic machine for ventilation of greenhouses works due to a change in the volume of working fluid inside the vessel. Volume, in turn, changes under the influence of ambient temperature. When it rises, the fluid pushes the piston to a certain height, thereby opening the window. When cooling, the reverse process occurs.
Since the liquid expands faster than it contracts, the closing process is "delayed". This phenomenon is called inertia and is the main disadvantage of these systems.
When installing, you should pay attention to the location of the machine - it is best to fix it at the top of the greenhouse. In this case, airing will occur faster, and cold air will not harm plants.
Advantages and disadvantages of hydraulic systems
Such equipment for greenhouses has the following advantages:
- its functioning does not require power sources;
- there is no need to control the operation of the device;
- the hydraulic system can be built at home;
- when using automation there are no unpleasant sounds and smells;
- even with an open window you can work in the greenhouse.
The main disadvantages of the hydraulic system are:
It is important to know that hydraulics takes into account the point temperature (that is, where the system itself is installed), and not the average in the greenhouse.
Pneumatic ventilators. Advantages and disadvantages
Automata of this kind work according to a simple principle: heated air from a sealed container is supplied to the piston through a tube. The piston, moving, opens the window. When the temperature decreases, the reverse process occurs - the cooled air is compressed and returned through the tube to the cavity of the tank. The piston returns to its place and the window closes. The greenhouse with automatic ventilation has the following advantages:
- complete independence from power sources;
- high performance;
- simplicity in installation and operation;
- low cost.
The following disadvantages are also distinguished:
- large installation dimensions;
- high inertia;
- The pneumatic system is highly responsive to changes in atmospheric pressure.
It is important to note that such an installation is almost impossible to make yourself.
Thermal drive. Principle of work and features
The thermal drive, for example, "Dusya San", is installed on the window of the greenhouse. It is also suitable for opening end greenhouse windows. This unit works without using power sources. There is a special fluid in the thermal cylinder that contracts or expands depending on the ambient temperature.
With increasing temperature, the working fluid “pushes” the piston to a height of 12 cm. At this point, the process of opening the greenhouse occurs. When the temperature decreases, the reverse process occurs - the liquid is compressed, and the piston returns to its place.
Such a greenhouse ventilation system operates in the range from 16 to 25 ° C. It is these temperatures that will be maintained inside the greenhouse.
The thermal actuator is capable of opening vents weighing up to 7 kg.
The package includes: the cylinder itself, levers and necessary connections, user manual.
The installation process is not difficult even for a beginner: it is enough to just fix the thermal cylinder between the greenhouse and the window leaf.
How to ventilate a greenhouse manually
In order to build automation for greenhouses with your own hands, you will need:
- vessels (banks with a volume of 3000 and 800 ml);
- covers;
- drill.
The construction process is quite simple: first you need to fill a larger vessel with water (800 ml) and roll it up with a lid. Then a hole is made in the center of the lid and a brass tube is inserted. The distance from the bottom to the beginning of the tube should not exceed 2-3 mm.
The hole around the tube is carefully treated with sealant. The cover for the second vessel should be kapron. A hole is also made in it, which is carefully sealed.
The outlet end from the first vessel extends almost to the bottom of the smaller can (2-3 mm from the bottom).
After the “manual” opener is ready, you should leave it in a warm, dry place until the sealant completely hardens.
In order for an ordinary building to become a greenhouse with automatic ventilation, you can build another device. This will require:
- metal canister;
- cylindrical vessel;
- balloon;
- material for the manufacture of the piston (foam or metal rod);
- rubber pipe;
- glue;
- sealant;
- scotch tape (preferably mounting);
- sewing machine bobbin;
- cord or fishing line.
Assembling an automaton comes down to a few simple steps:
- To begin with, you should paint the canister (preferably in a dark matte color). Then in the cover you need to make a hole for the pipe. All openings are carefully sealed.
- Next, make a cylinder. For this, a pipe of suitable size is rolled up from polycarbonate. The ends of the pipe are worked out by glue. The bottom for the cylinder is made of the same material. A hole is made in the center of the bottom to accommodate the stem. Then make the cylinder cover. The rod guide can be made from a plastic tube. For fixing parts, glue is used. The lid is best made removable.
- For the manufacture of a pneumatic piston for a greenhouse ventilation machine, an inflatable ball, adhesive tape and rod material are used. Stick on adhesive tape to the stem, then put on a balloon. A circle of suitable diameter is cut from the foam. Its ends should be pasted with tape. When choosing the diameter, it is important to take into account the size of the glass, and to reduce the friction between them, the surface of the walls is treated with petroleum jelly. At this stage, it is necessary to attach a rod to the foam circle.
- The final step will be the manufacture of the rocker arm and the assembly of the structure. In this case, the rocker will be platinum with holes at the ends. The smaller hole is for attaching the transfer bowstring, and the larger is for attaching to the axis (you can use a nail for the axis).
The assembly order is as follows:
- The receiver is mounted under the ceiling of the greenhouse.
- The cylinder is mounted in any convenient place.
- The pulley is mounted on the wall or on a separate tripod.
Next, from the beam to the desired window, a transfer tape (bowstring) is brought in and the system is set up.
It is as follows:
- The nozzle is attached to the ball, which is inflated, and then connected to the receiver.
- Then install the piston.
It is important to note that the adjustment of the mechanism should be carried out at an ambient temperature of 15 to 18 ° C.
Automatic machines for ventilation of greenhouses. Overview
The most popular in the modern market are:
- Autovent XL. The English device is designed to open small windows (up to 5.5 kg) to a height of 30.5 cm. The machine operates at a temperature of 12 ° C.
- Autovent MK-7. It has the same characteristics as the previous one. The difference lies in the design: Autovent MK-7 is reinforced with three springs at once.
- The powerful Danish Megavent apparatus opens the air vents to a height of up to 45 cm. The weight of the structure to be lifted can be up to 24 kg.
- Super Autovent MK-7 is a popular greenhouse ventilation machine. Its characteristics are as follows: carrying capacity - up to 16 kg, window opening height - up to 45 cm. It should be noted that in this unit you can independently adjust the operating temperature range.
- The Tuymazy automation system is designed to be installed both on the window and on the door. It is worth noting the unusual carrying capacity, which is 100 kg. The window at the same time rises to a height of 40 cm. The range of operating temperatures is from 16 to 25 ° C.
- "Dusya San." It is located in an affordable price category and is considered quite an effective and reliable device.
- The hydraulic cylinder "Upofar" is also able to withstand the large weight of the window and a fairly wide range of operating temperatures. It is worth noting that after installation, the cylinder does not need maintenance and repair for about 5 years.
- Danish Gigavent. The device for ventilating greenhouses is capable of lifting 30-kilogram air vents to a height of 45 cm. The device is also equipped with an anti-disruption system and is easily mounted on any type of air vents.
Automatic machines for ventilation of greenhouses. Reviews
The following systems are considered the most popular:
- "Banking". Home-made design consists of two cylindrical vessels - cans. The volume of 3000 and 800 grams, respectively. Home-made design is widespread among users. The main advantages are: availability in materials and price category, ease of installation and operation. The disadvantage is that such a system is intended only for window leaves that open along the horizontal axis.
- "Dusya San." The thermal drive has positive qualities: the installation process is very simple, and with proper installation, the device will last for many years. Among the disadvantages are poor resistance to strong winds and low temperatures. Also, the thermal drive does not withstand loads of more than 7 kg.
- The hydraulic machine for ventilating greenhouses "Ufopar" also deserves special attention. The main advantages are: no need for adjustment, cylinder resistance to temperature extremes. Accordingly, there is no need to remove it for the winter period (in order for the mechanism to not work, it is enough to tighten only one nut). "Ufopar" reacts to a change in ambient temperature, so the process of opening and closing the window is several times a day. The main disadvantages are: the difficulty in choosing the installation site and installation, the large weight of the structure.
- Automatic machine for ventilation of greenhouses "Opener-Lux". Customer reviews report that this device takes into account the ambient temperature and regulates the opening height of the window. Also, the machine is suitable for any design. The window can be opened up to a height of 45 cm. A positive aspect is the possibility of installing a ventilator on any window (both ceiling and end) and on the door. Installation of automation is simple and can be done even by a beginner. Among the shortcomings are high cost and overall dimensions.
- Thermal drive T-34. A modern device has the following advantages: increased service life, complete autonomy, and simplicity of design. Also, the thermal drive is quite powerful and is capable of opening vents weighing up to 10 kg. T-34 fires at an ambient temperature of 24 ° C. The machine is suitable for any type of modern greenhouses. The disadvantages are: high cost, size and the need for dismantling for the cold season.
When choosing equipment for automatically opening window leaves or doors, one should take into account not only the parameters of the greenhouse, but also the climatic zone, the type of plants and the season.