Series PLT Potable Water Expansion Tanks are to absorb the increased volume of water created by spring expansion and to maintain harmonious pressure throughout the drink water supply system. Series PLT tanks a pre-pressurized steel tank with an expansion membrane that prevents contact of the water with the air in the tank. This loss of air to the water and ensures monthlong and untroubled life for the system. These tanks may be with all types of related Fired tropical Water Heaters -LRB- gas, oil or galvanizing -RRB- and tropical water storage tanks. listed and ANSI/NSF 61 credentialed. Maximum : 150psi -LRB- 10 bar -RRB-.