Using an old refrigerator to create an incubator is one of the most popular solutions among amateur poultry farmers, allowing you to get a functional apparatus with minimal financial investment. The body of a household refrigerator is ideal for this purpose due to its tightness and, most importantly, excellent thermal insulation, which allows you to maintain a stable temperature even when the power is turned off.
Homemade incubator of this type can hold several times more eggs than standard store-bought models of the same price segment, which makes it economically viable for a small business or large farmstead. In this article, we will analyze in detail all the stages of conversion, the choice of heating elements and ventilation systems, so that you can create a reliable apparatus for hatching chicks.
The main advantage of this design is the ability to completely customize the internal space to suit your needs, be it hatching chickens, ducks or quails. However, for the device to work correctly, it is necessary to strictly observe the technical requirements for heating and air circulation, since stable conditions are critical for embryos.
Selection and preparation of the refrigerator body
To create a high-quality incubator, old Soviet refrigerators with a metal body are best suited, since they have thicker walls and better insulation compared to modern plastic ones models. Before starting work, you must thoroughly wash the inner chamber, remove all shelves, drawers and the freezer, if it is removable, leaving only a clean metal box.
Particular attention should be paid to the condition of the sealing rubber on the door, since tightness is a key factor in heat retention. If the rubber is cracked or has lost its elasticity, it must be replaced or restored with special compounds, otherwise heat will escape and the controller will work with overload.
⚠️ Attention: Do not use refrigerators that have leaked freon or refrigerant with a strong odor inside, as residual gas can be toxic to developing embryos and require long-term ventilation or complete replacement of seals.
If you are using a model with a freezer inside the main volume, it is better to dismantle it to increase the usable space, and seal the resulting hole with a sheet of foam or plywood with insulation. The inner walls can be additionally sheathed with foil penofol, which will improve heat reflection and help distribute heat flows inside the chamber more evenly.
Required materials and tools
Assembling an incubator requires a certain set tools and components that will ensure durability of the structure and safety of operation. The basis of the control system will be an automatic thermostatwhich will control the operation of heating elements and fans, maintaining the set parameters with high accuracy.
To implement the project you will need the following set of materials:
- 🔌 Thermostat with a temperature sensor (for example, models series STC-1000 or XH-W3001) for precise climate control.
- 🔥 Heating elements: incandescent lamps, nichrome spiral or special ceramic heaters without glow.
- 💨 Fans for air circulation (computer coolers 12V or 220V) to prevent stagnation of air masses.
- 🥚 Egg trays with an automatic or manual turning mechanism for the correct development of the embryo.
- 🌡️ Backup thermometer (hygrometer) for independent verification of electronic readings.
It is important to correctly calculate the power of the heating elements, since a too powerful heater will lead to sudden temperature changes, and a weak one will not be able to warm up the volume in the cold season. For a standard two-chamber refrigerator with a volume of about 200 liters, 4-6 incandescent lamps of 40-60 W or an equivalent heating element with a ceramic insulator are usually sufficient.
All electrical connections must be made in compliance with fire safety rules, the wires must be insulated with heat-resistant materials, and the wiring itself must be brought out through a sealed hole. The use of automatic switch in the power circuit will protect the structure from short circuits and network overloads.
Installation of the heating and ventilation system
The heating system is mounted, as a rule, in the lower part of the refrigerator or on the side walls, since Warm air naturally rises, creating the necessary convection. When using incandescent lamps, they are placed at a distance of at least 15-20 cm from the eggs to prevent local overheating of the shell, which can destroy the embryo. Ventilation is a critical element, without which uniform gas exchange necessary for the development of chicks is impossible. The fans are installed in such a way as to create a circular flow of air, blowing the heating elements and spreading heat throughout the entire volume of the chamber without creating strong drafts on the trays.
Ventilation is a critical element, without which uniform air circulation and gas exchange necessary for the development of chicks. The fans are installed in such a way as to create a circular air flow that blows over the heating elements and distributes heat throughout the entire volume of the chamber without creating strong drafts on the trays.
☑️ Checking the climate system
The optimal solution is to install fans at the top of the chamber or on the sides, aimed at the heating elements, which allows you to quickly mix the warm currents. The speed of the air flow should be moderate: if the feathers of fluff brought to the trays flutter strongly, it means that the ventilation is excessive and can cause the eggs to dry out.
⚠️ Attention: It is strictly forbidden to place the thermostat temperature sensor directly on the heating element or in the path of the direct flow of hot air from the fan, otherwise the readings will be incorrect.
Organization of egg turning and trays
For successful hatching of birds, it is necessary to ensure regular egg turning, which prevents the embryo from sticking to the shell and ensures uniform heating. In homemade incubators from a refrigerator, lattice trays are most often used, which are installed at an angle and change position using a mechanical drive or manually.
The automatic flip mechanism can be made from an electric motor from a car windshield wiper or a gearbox, which, through a rod system, will tilt the trays 45 degrees in each direction. This requires additional adjustment of the time controller, but greatly facilitates the work of the poultry farmer, especially at night.
Trays should be made of wood or plastic with a mesh bottom to ensure air access from all sides, and have sides to prevent eggs from falling out when tilted. The vertical distance between trays should be at least 15-20 cm to ensure high-quality heat circulation between tiers heat circulation between tiers.
If automation of the process seems complicated to you, you can implement a simplified scheme with manual turning by making the trays removable or mounted on an axis with a handle on the outside housings. In this case, you will have to open the door 3-4 times a day, which leads to heat loss, so the process must be worked out to speed and precision.
Secrets of the mechanics of turning
To smoothly tilt the trays, use counterweights or a lever system to reduce the load on the engine. The angle of inclination should be strictly 45 degrees: a smaller angle is ineffective, and a larger one can lead to damage to the air sac of the egg.
Humidity control and temperature conditions
Maintaining optimal humidity is the second most important parameter after temperature, which directly affects the hatchability and health of the chicks. In homemade incubators, humidity is regulated by the evaporation of water from open trays, the surface area of which can be changed, as well as by ventilating the chamber.
To control the parameters, use the following table of modes, which is basic for hatching chicken eggs, but can be adjusted depending on the breed and type of incubation:
| Period (days) | Temperature (°C) | Humidity (%) | Turnover | Ventilation |
|---|---|---|---|---|
| 1-7 | 37.8 - 38.0 | 55-60 | Every 2-4 hours | No |
| 8-14 | 37.8 | 50-55 | Every 2-4 hours | 5 min (cooling) |
| 15-18 | 37.5 - 37.6 | 50-55 | Every 2-4 hours | 10 min (cooling) |
| 19-21 (Roost) | 37.0 - 37.2 | 65-70 | Stops | No |
To increase the humidity, containers with water are installed in the lower part of the refrigerator, into which evaporators made of fabric or sponges can be immersed to increase the evaporation area. Reducing humidity is achieved by replacing the water with colder water or temporarily opening the door to exchange air masses.
Testing and startup incubator
Before laying the first batch of eggs, it is necessary to test run the incubator empty for 2-3 days to ensure the stability of all systems. During this period, the uniformity of heating at different points of the chamber, the operation of the thermostat and the absence of overheating of the wiring or case are checked.
Place several control thermometers at different levels and in different corners of the refrigerator to identify “cold” or “hot” zones that require adjustment of the position of fans or heaters. If temperature differences exceed 0.5 degrees, it is necessary to modify the system air circulation or add reflective screens.
Pay attention to the operation of the door: it should close tightly, but without excessive effort, and the viewing window (if you cut it) should not become bridge for heat leakage. Only after the device stably maintains the set temperature throughout the day without your intervention can you begin to calibrate the sensors and prepare for the biological process.
How often should the incubator be ventilated?
In the first half of incubation, ventilation is minimal, but in the second half (after 10-12 days) the embryos begin to actively consume oxygen and produce heat. From this period, it is recommended to open the door for 5-15 minutes 1-2 times a day to cool and exchange air, especially if the design does not have active supply ventilation.
Is it possible to use an incubator in an unheated room in winter?
Using a homemade incubator in an unheated room in winter is possible, but requires additional external thermal insulation of the housing (for example, foam sheathing) and installation of more powerful heating elements. However, sudden changes in external temperature can destabilize the operation of the thermostat, so it is better to place the device in a room with a temperature not lower than +15°C.
What to do if the electricity is turned off?
Due to the good thermal insulation of the refrigerator, the temperature inside will drop slowly. In case of a power outage, close the door tightly, cover the refrigerator with a blanket and try not to open it unless absolutely necessary. For short-term heating, you can use hot (not boiling water!) heating pads, wrapped in fabric, placed on top of the trays.