What is the purpose of the vent valve on a hot water boiler?

The vent valve on a hot water boiler serves a critical purpose in maintaining the efficiency and safety of the system. Specifically, it is designed to vent trapped air from the boiler. When air becomes trapped in the system, it can prevent water from circulating effectively, leading to inefficiencies and potentially causing overheating in certain areas of the boiler. By allowing air to escape, the vent valve ensures that the water can fill the system properly and that the heating can occur evenly throughout the boiler.

Additionally, venting trapped air helps to maintain appropriate water levels within the system. If air pockets are not removed, they can lead to inaccurate water levels, which in turn can affect both heating performance and the overall operation of the boiler. Therefore, the vent valve plays a vital role in the functionality and safety of hot water boilers.