AMTROL ST-5 Thermal Expansion Tank for Water Heaters - 2 Gallon Capacity, Pre-Charged, for Residential Plumbing Systems - Perfect for Home Water Heater Protection and Hydronic Heating Systems

Amazon.ca Product Description Amtrak invented the thermal expansion tank to control pressure build-up in closed, hot water systems. This prevents the water heater pressure relief valve from opening, saves energy and eliminates a potential safety hazard. All thermo-x-troll expansion tank. From the Manufacturer Amtrol invented the thermal expansion tank to control pressure build-up in closed, hot water systems. This prevents the water heater pressure relief valve from opening, saves energy and eliminates a potential safety hazard. All Therm-X-Trol expansion tank