What is a GREY expansion vessel used for?

Expansion tanks are also known as expansion vessels and are used to protect closed water heating systems and domestic hot water systems from excessive pressure. As the water heats up the pressure can increase by 4.5% so they are a very important part of any sealed system.

How do expansion vessels work?

How does an expansion vessel work? When heated, water molecules vibrate and move, causing the water to expand in size. This means that water inside the boiler will expand upwards and, if left unchecked, increase the pressure in the system to dangerous levels.

What is the difference between a white and red expansion vessel?

In a red vessel, the membrane forms two chambers within the vessel. Water in the vessel is in contact with metal body and membrane. Water entering the vessel is likely to be hot and membrane will not fail during ‘hot’ operation. White vessel has a bladder.

What are blue expansion vessels for?

The Imera Blue Potable Expansion Vessels are built from different materials than Red Heating Expansion Vessels to ensure that the water is contaminant free and safe for human consumption. The most common use for a blue expansion vessel in a potable application such as an Unvented Water Heater or a Pumped System.

What pressure should a sealed heating system be?

between 1 and 1.5 bar
When the heating system is cool, the pressure should be between 1 and 1.5 bar on the pressure gauge (the indicator needle would usually be in the green section). If pressure is below 0.5 bar (down in the red section), water has been lost from the system and must be replaced.

What pressure should hot water expansion vessel be?

between 50 and 60 PSI
The recommended water pressure is between 50 and 60 PSI. Thermal Expansion Tanks contain an air bladder which is pressurized with air, and expands and contracts to absorb the expanded water from the water heater.

Can I use white expansion vessel for heating?

Answer. Yes, it is: the expansion vessels suitable for potable water applications can be installed on central heating systems.