Thanks to the appropriate preparation of the solar collector and boiler installation, it increases the efficiency of the installation, improving the speed of water heating (even in large quantities), while allowing for a reduction in electricity bills. However, the domestic water heating system will only fulfill its function when it is connected in accordance with the art, based on high-quality components. How to choose a solar collector for a water boiler? How to prepare the installation and connect the solar collector to the tank? We explain.
Check out the solar collectors at the Onninen wholesaler
Selection of appropriate pipes for solar collectors
When selecting pipes for a solar installation, remember their diameter, length, and the material they are made of. This is important because the loss of energy supplied by these elements should not affect the efficiency of water heating.
The installation most often uses flexible pipes made of steel or copper pipes. The above-mentioned materials guarantee a stable temperature of the energetic glycol and ensure the appropriate pressure of the working fluid.
The pipe diameter cannot be too low or too high. Too tight pipework makes the installation ineffective. Increasing the glycol temperature increases the heat loss of the solar collector, which in turn results in problems with heating the water in the tank. On the other hand, pipes that are too wide reduce the flow rate of the liquid and lead to air accumulation, which also effectively hinders heat production.
Experts indicate that the pipe diameter should allow glycol to flow at a speed of 0.40-0.70 m/s. Such parameters are provided by pipes with a diameter of about 42×1.5 mm (for copper pipes) or wider for steel and flexible pipes (corrugated with markings DN16, DN20 and DN25, while stainless steel with a maximum diameter of 100 mm). The length depends on the energy demand and the distance between the collector and the boiler .
Appropriate collector power for the boiler and home requirements
It is worth remembering that the key factor when selecting specific elements is the demand for thermal energy. Here, the area of the house and the number of people who will use the water heated by the boiler are taken into account.
The following parameters are necessary to calculate the tank capacity and the power and surface area of the solar collector:
-
Daily demand for hot water per person – calculated according to the demand table (available e.g. on the Internet) - Number of people using the tank – for a household or utility area.
- Hot water temperature at the draw-off point – starting from the boiler.
- Cold water temperature – supplied to the boiler from the source.
- The maximum water temperature that the boiler can provide is usually around 50/60 degrees.
The minimum capacity of the boiler is the domestic demand per person multiplied twice, the number of people, and the difference between the temperature of the hot water at the draw-off point and the cold water. The result should be divided by the difference in the temperature of the water in the tank and the cold water.
In Poland, it is assumed that for every 50 liters of boiler there is 1 square meter of active collector surface. If the demand for the minimum capacity is 500 liters, then an installation based on 10 square meters of collector should be created.
The power generated by the solar collector should be matched to the water heating time and the boiler capacity. In a boiler for an average family with a capacity of 120 liters and a power of 2kW, the water is heated for 2.5 hours. The collector must guarantee the full energy demand during this time.
How to properly connect solar collectors to each other?
A single solar collector can be, for example, about 2 square meters, so five such devices are required for full efficiency when working under a solar installation. They must be mounted relatively close to each other so that they can be effectively linked together
Special connectors are used to connect the collectors, enabling the joint condensation of the energy produced. It is also necessary to use stainless steel screw connections and clamps. Sometimes manufacturers have dedicated solutions created for the panels they prepare. In such a case, you should use the connections recommended by the manufacturer and rely on several panels of one brand.
Correct setting of solar panels for hot water and connection of the installation
The device setting is just as important as the correct connection of the solar collector. It should be corrected depending on the season. In the case of seasons with average sunlight (e.g. spring, summer, autumn), the angle of setting in relation to the sky should be 45 degrees. In the case of very sunny days, a correction to 30 degrees is required. In winter, late autumn and early spring, the collector should be set to 60 degrees.
After installing the collector and securing it to the substrate, you can continue with the installation. To do this, you will need an adapted boiler (with two coils), an expansion tank (designed to equalize the pressure in the collector system), a controller, a pump and a heat exchanger. The power of all parameters must be correlated. A pump that is too weak will not be able to provide the appropriate glycol pressure during the collector's operation.
Effective protection of collectors against overheating
Overheating of a solar installation most often occurs in the summer, when the solar collector processes a very large amount of heat energy. To prevent this situation and protect the device from too high temperatures, specialists recommend covering the device when the collecting vessel (boiler) is not in use (e.g. during a vacation or renovation work).
To cover the collector, it is necessary to use reflective foil or a tarpaulin that will stop the effects of solar radiation.
Solar collectors and boilers in the Onninen wholesaler
If we want to connect a solar collector and enjoy an efficient installation, it is worth investing in boilers and solar panels from the Onninen installation wholesaler . Devices such as the Immergas EP 2.0 V2 solar collector , the Wolf TopSon F3-1" solar collector, the Vertical "TopSon F3-1" and the Clage 50L capacity tank guarantee high efficiency and provide access to cheap, hot water in public buildings or private homes.
By installing a tank and a collector adapted to the installation, we can enjoy hot water at any time of the year, effectively reducing electricity bills. However, the efficiency of the installation also depends on the correct connection of subsequent parts and each