There are two types of expansion vessels in the solar system:
- expansion vessel of the solar system (red)
- expansion vessel for domestic hot water (white or blue)
The expansion vessel of the solar system (red) secures the system at the moment when the pressure within it rises. The vessel is equipped with a special membrane and makes it possible to level off the changes in the solar liquid thermal expansion and maintain the pressure at the required level. It is a welded steel container, divided by an inside membrane separating solar liquid from gas. The adequate pressure of the gas part stabilizes the pressure of the entire system.
Additionally, pressure growth in the system is prevented by means of a safety valve mounted on the pump unit.
The expansion vessel for domestic hot water (white or blue) is a similar appliance to the expansion vessel of the solar system (red) but it is used to secure the domestic hot water system at the moment when the water volume in the tank increases because of the temperature growth. This vessel makes it possible to level off the water thermal expansion without water loss and maintain the pressure of domestic hot water at the required level.