expansion tank water level valveExpansion Tank Water Level Valve - Airtrol Valves help maintain the proper level of water inside expansion tanks. The valve allows air and water to flow into the tank where the air level in the tank allows for a cushion for expansion and contraction of the water in the loop. Since liquids do not compression air is used as the compression medium in the expansion tank to allow the loop to expand and contract without setting off pressure relief valves.

Expansion Tank Water Level Valve

The B&G Airtrol Valve is used in compression type expansion tanks without a bladder in the tank. Bladder type expansion tanks work differently than compression type expansion tanks. The B&G Airtrol valve takes the guesswork out of ensuring the expansion tank has the proper level water and air inside the expansion tank. The proper level of water in the tank is very important and this valve helps you get it right the first time. This is important to allow the pressure in the system to expand and contract based on thermal expansion of the liquid in the system.

Expansion Tank Water Level Valve - Maintenance & Service

This valve makes it easier during a maintenance or service call to ensure the proper water level. The water level inside the expansion tank. There are some expansion tanks such as the one above, that do not have bladders. Nor do they have this Airtrol valve so the maintenance or service technician has to guess how much water should be in the expansion tank. Since bladder tanks do not need this feature bladder type expansion tanks would not have this valve. The bladder type expansion tanks use a bladder and air pressure to maintain proper levels inside the tank.

Bladder expansion tanks are always filled to some degree. The bladder allows the water to expand and contract for thermal expansion. Whereas if a steel expansion tank (bladderless) is completely full there is no expansion of the system. Furthermore, problems definitely occur if it becomes fully waterlogged. Therefore, this valve is nearly a necessity to ensure proper levels in bladderless expansion tanks. Additionally, it takes the guesswork out of the proper water level in the expansion tank.

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Expansion Tank Water Level Valve

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