Description

Solar water heating element is a special electric component that converts electric energy into heat energy. Because of its cheap price, convenient use, convenient installation, no pollution, it is widely used in various heating occasions. It is used in commercial water heater.

Basic working principle.
Electrical-to-thermal conversion: Inside the heating element, there is a high-resistance alloy wire (such as nickel-chromium alloy). When powered on, it generates Joule heat (Q = I2Rt). The heat is transferred to the metal casing through a heat-conducting medium (such as magnesium oxide powder), and then the water in the water tank is heated.

Temperature control linkage: It is linked with the temperature sensor of the solar system. When the water tank temperature is lower than the set value (such as on rainy days or at night), the electric heating is automatically activated; when the temperature reaches the set value, the power is cut off to avoid overheating.

Common types
(1) Immersion heating element
Structure: A metal tube (made of stainless steel or copper) is directly inserted into the water tank, with the internal heating wire insulated and encapsulated.
Installation location: The side wall or bottom of the water tank.

Feature: Heating is fast, but long-term soaking is prone to scaling (regular cleaning is required).
Make sure it is fully submerged in water; otherwise, it may be damaged by dry burning.

(2) Dry-burning heating element
Structure: The heating element is isolated from the water tank water and heats indirectly through the metal wall.

Feature:Prevents dry burning, has a longer lifespan, but has a slightly lower thermal efficiency.
Commonly found in high level solar water heaters or pressure tanks.

(3) Instant heating element
Principle: Water is instantly heated as it passes through the heating tube (with a high power, usually 3-6 kW).
Application: Mostly used as an auxiliary heating module for solar systems, and requires a matching high-current circuit.

Collaboration with the solar energy system
Priority solar heating: During sunny days, the vacuum tubes collect heat and the electric heating does not start.
Automatic switching to electric auxiliary heating: When the solar energy fails to reach the set temperature (such as in winter or on cloudy days), the thermostat powers on the heating tubes.
Energy-saving mode: Timed heating can be set (such as during off-peak electricity hours) to reduce electricity costs.

Advantages:
Ensures round-the-clock hot water supply, compensating for the instability of solar energy.
Installation is simple and the cost is low (compared to pure heat pump assistance).

Disadvantages:
High power consumption (higher electricity bills for long-term use).
Scaling problem (requires regular cleaning in hard water areas).

1 As to the factors affecting the quality of solar water heater electric heating element , the quality of the material is very important

2. The reason. Reasonable selection of raw materials of electric heating tube is the premise of guaranteeing the quality of electric heating tube.

3.Pipe selection principle: temperature resistance, corrosion resistance.

4 resistance wire selection: Cr20Ni80.

5. Selection of magnesium oxide powder: industrial grade magnesium oxide powder

6 Sealing material selection: silicone oil +704 sealant.

Currently, the solar water heating element on the market are generally equipped with various temperature controllers or thermal protectors. These accessories enable the heated water to cut off the circuit and stop heating once the temperature at the test point reaches the set value; when the water temperature at the test point drops below the lower limit value, this device will automatically close.

In fact, once a heating element is installed into the tank of a solar water heater, it becomes a storage-type electric water heater. Storage-type electric water heaters have developed a complete production technology management system and execution standards after long-term application. This type of storage-type water heater should be equipped with an automatic reset thermostat, and it must also be equipped with a non-automatic resetter specifically designed to prevent dry heating. When the heated water in the water heater is less than a certain amount, this non-automatic resetter will forcibly cut off the circuit and stop the heating. Only after the efforts of relevant personnel to confirm that the accident state has been eliminated can the manual reset be performed, and then the system can be restarted. This prevents the serious consequences of dry burning accidents

Product detail