Onyx 100L Red Heating Vessel 1.5 Bar ONYX100LHEAT

The Onyx 100L Red Heating Vessel is a 100 litre expansion vessel charged to 1.5 bar, supplied within the Onyx expansion vessel range. It absorbs the increased volume of water as a sealed heating system heats up, limiting pressure rise and protecting the system from excessive expansion. The vessel is identified by its red casing, which distinguishes it as a heating rather than potable water unit.

• Boiler or system pressure rises sharply when the heating is running and drops again once it cools
• Water, rather than air, is released when the charging valve is depressed
• The system pressure relief valve discharges during normal heating cycles
• Visible corrosion, pitting or damp patches on the vessel shell or connections
• Repeated topping up of system pressure with no visible external leak

• Confirm the required vessel volume matches the system design before ordering
• Check that the 1.5 bar rating is appropriate for the system's cold fill and operating pressures
• Verify the available installation space, as a 100 litre vessel requires adequate clearance
• Check the vessel connection size and orientation against the existing pipework arrangement