Which type of tank is required to be installed in every hot water system?

In every hot water system, an expansion tank is essential due to the nature of how liquids expand when heated. Water expands as it is heated, which can increase pressure within the hot water system. If this pressure increase is not managed, it can lead to system failures or even hazardous conditions.

The expansion tank serves as a safety feature that absorbs the extra volume of water and relieves pressure in the system. It is typically installed in the hot water supply piping and maintains system integrity, helping to prevent leaks, burst pipes, and damage to appliances. Having an expansion tank ensures that the water heating process operates smoothly and safely, complying with code requirements for hot water systems.

Other types of tanks mentioned, like a cold water tank or storage tank, serve different purposes, such as holding water before it is heated or storing hot water for use, but they do not specifically address the pressure variation caused by thermal expansion. A pressure tank, on the other hand, might be related to systems involving well water or specific pressure settings but is not standard for managing the expansion in hot water systems.