Each owner of a suburban area, for sure, would not refuse the prospect of harvesting throughout the calendar year. Of course, taking into account the peculiarities of the domestic climate, this will require some effort to build a heated greenhouse. Do-it-yourself water heating of a greenhouse is one of the most reliable and common ways to achieve the indoor temperature necessary for the effective growth of plants, the formation of ovaries and fruits.
Advantages and features
Water heating of the greenhouse is characterized by the following positive features:
- Constructive simplicity, the system can be easily implemented even on a large area object.
- All available fuels are used. The heating method is selected in accordance with the financial capabilities of the owners, the characteristics of the area, and the presence of highways nearby.
- Water is a unique medium in terms of heat capacity, the reached temperature of the liquid is maintained for a long time even after the power is turned off, which saves fuel and eliminates sudden temperature changes that are detrimental to plants.
- The water method does not provoke a drop in air humidity (this minus is typical for fan heaters and other air heating devices, the heating elements in which are not covered with special covers that prevent oxygen from burning out), that is, a microclimate is formed that is most favorable for flora.
- Pipes can be laid in the ground to achieve root heating, which is important for some types of crops.
The disadvantage of the method, in fact, is one. An abrupt stop in the fuel supply will lead to freezing of water in the pipes, which will provoke the formation of ice with the subsequent destruction of the entire circuit.
Please note that before you purchase a heating boiler and other devices, you should be puzzled by increasing the thermal insulation performance of the object. Closing gaps, eliminating drafts, laying panels based on cellular polycarbonate, gluing special polystyrene on a foil backing to the plane — all these measures will help to achieve the preservation of accumulated heat, which will reduce overall fuel costs.
Also read: We make a winter greenhouse with our own hands.
When forming a water heating system, the following equipment and elements are used:
- Heat generator (boiler or furnace).
- The pump is used to constantly maintain a sufficient water flow rate. Some schemes imply natural circulation, but it is unlikely that such a method can be implemented on large objects.
- Ground circuit for the transfer of thermal energy. This water circuit heats the soil, it is installed to a depth of about 30 centimeters. It is allowed to use any pipes, but it is better to choose models based on polypropylene or metal-plastic. Pure metal, when kept in constantly moist soil, will gradually begin to rust, even with a protective coating. If we talk about the temperature of the pipes, then 30-40 degrees are sufficient, this is quite enough for a real increase in plant yields and a reduction in the growing season.
- Air heating circuit. Pipes, radiators, batteries, located along the entire length of the agricultural structure.
- An expansion tank that compensates for the expansion of water during the heating process, preventing critical overpressure in the system.
Main article: Greenhouse heating with infrared heaters
The scheme for forming a heating system in a greenhouse with your own hands is as follows:
- The place where the furnace or boiler will be located is determined. This point must be carefully considered so that the bulky structure does not interfere with the passage, and there is enough space nearby to store fuel. However, do not forget that the boiler itself is a source of thermal energy, so it is often placed right in the middle of the object.
- Pouring the foundation for the boiler. If it is planned to install a brick structure, then the foundation is made on the basis of concrete. A metal boiler or a potbelly stove does not need to be filled, it is enough to find a metal sheet of sufficient thickness, and it will become a reliable support.
- Installation of a pipe for the removal of combustion products. It is necessary to ensure that all joints are hermetically sealed to prevent gases from entering the room.
- Connecting pipes to the boiler. Metal pipes are connected directly to the unit, this is the only way to guarantee the necessary reliability and level of resistance to loads. After 100-150 centimeters from the beginning, it is allowed to connect selected main pipes, including those based on polypropylene.
- Expansion tank installation. For it, the highest point in the room is selected, preferably directly above the heat source. Before entering the tank, an automatic machine with a shut-off valve and a pressure indicator are mounted.
- Pipe laying, installation of radiators and valves. In the event that a separate shut-off valve is placed on each battery, then a jumper must be mounted between the inlet and outlet pipes. Otherwise, turning off one radiator will stop the entire system.
If we talk about the need for a circulation pump, then a small farm object can be successfully heated without it, but for structures with a total area of 100 or more squares, this accessory is necessary.
Separately, it is worth mentioning some of the nuances of underground heating in a greenhouse. Heating in a greenhouse of this type is most effective if you follow some rules:
- Laying polyethylene pipes should be carried out in a pillow of carefully washed sand. The recommended pillow thickness is about 15 centimeters. This is done in order to achieve more uniform heating of the soil;
- To prevent wasted energy, polystyrene thermal insulation is laid;
- The layer of fertile soil should be at least 30 centimeters.
So, it is not necessary to use a heater to heat the greenhouse — the device is simple, but too efficient and economical. It is quite possible to equip your site with a productive water system, all the costs relevant at the installation stages will be justified in just a couple of seasons!