The expansion tank is an important component in the HVAC system. It accommodates the expansion of the system water in the heating system, and also acts as a constant pressure and hydrates the system. It is usually made of steel, usually round or rectangular. Due to the thermal expansion and contraction of the water in the heating system, when the hot water heats up, the volume of water in the system increases. When there is no part of the expansion of the water, the water pressure in the heating system increases, which will affect the normal operation. . The water expansion amount of the expansion tank accommodating system can reduce the water pressure fluctuation caused by the expansion of the water, and improve the safety and reliability of the system operation. When the system leaks water for some reason or the system cools down, the water level of the expansion tank Drop and replenish the system. The expansion tank can also stabilize the pressure of the system and remove the air released by the water during the heating process.
Calculation of tank volume
V=αΔtVa
Where V is the effective volume of the expansion tank (ie the volume corresponding to the height between the inspection tube and the overflow tube), L;
Α-water unit volume expansion coefficient, α=0.0006;
Δt—Consider that sufficient water capacity should be stored frequently in the expansion tank to compensate for the volumetric shrinkage of the water in the system. The maximum fluctuation of the water temperature in the system is generally calculated at 20 °C water temperature;
Va—the amount of water in the system, L.