The Zilmet pressure vessels are made up of a replaceable Butyl diaphragm mounted in a mild steel shell eliminates any contact between the water and the steel shell of the vessel. All units up to and including 24 litre sizes are suitable for a working pressure of 8 bar and the larger vessels 10 bar (except 1000LV). The vessel is supplied pre-charged with air, but this pressure may require adjustment to suit the site conditions this adjustment must made with the vessel isolated from the system and before filling with water.
