When the gas overflows in the system, the gas will climb up along the pipeline. The final gathering is at the highest point of the system, and the exhaust valve is generally installed at the highest point of the system. When gas enters the valve cavity of the exhaust valve and gathers at the upper part of the exhaust valve, the pressure will rise with the increase of gas in the valve. When the gas pressure is greater than the system pressure, the gas will make the water level in the cavity drop, and the buoy will open the exhaust port with the drop of water level. After the gas is exhausted, the water level rises, and the buoy also rises, closing the exhaust port.
Similarly, when negative pressure is generated in the system, the water level in the valve cavity drops and the exhaust port opens. At this time, the external atmospheric pressure is greater than the system pressure, so the atmosphere will enter the system through the exhaust port to prevent the harm of negative pressure.
So when the pressure of each part of hot water is too high, the exhaust valve will open, and whoever flows out will flow out.
Extended data:
Maintenance and descaling of water heater
1, the system regularly discharges pollutants to prevent pipeline blockage; And clean the water tank to ensure the water quality is clean. When discharging sewage, as long as the water inflow is normal, just open the drain valve until clean water flows out of the drain valve.
2. Regularly remove the dust and dirt on the transparent cover plate of the solar collector, keep the cover plate clean and ensure high light transmittance. Cleaning should be carried out in the early morning or evening when the sun is not strong and the temperature is low, so as to avoid the transparent cover plate being crushed by cold water.
3. Pay attention to check whether the transparent cover plate is damaged, and replace it in time if it is damaged.
4. For vacuum tube solar water heater, always check the vacuum degree of vacuum tube or whether the inner glass tube is broken. When the barium-titanium getter of vacuum tube turns black, it shows that the vacuum degree has decreased and the collector tube needs to be replaced.
5. Vacuum tube solar water heater not only cleans the vacuum tube, but also cleans the reflector at the same time.
6. Inspect the pipelines, valves, ball valves, solenoid valves and connecting hoses for leaks, and repair them in time if any.
7. If the heat absorption coating of the heat collector is damaged or falls off, it should be repaired in time. All supports and pipes should be painted with protective paint once a year to prevent corrosion.
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