Watts 0066606ETX-30 Pressurized Expansion Tank

Description:

The Watts 0066606 ETX-30 Pressurized Expansion Tank is a diaphragm-type expansion tank designed to control the thermal expansion of water in closed-loop hydronic heating systems and maintain system pressure below the relief valve setting. Commonly installed in residential and commercial hydronic heating systems, boiler plants, radiant heating systems, HVAC equipment, hot water circulation systems, and mechanical room installations requiring thermal expansion control. Maintenance technicians, HVAC contractors, facility engineers, and system integrators use this expansion tank for system upgrades, replacement projects, preventive maintenance, and new hydronic heating installations.

Applications:

The Watts ETX-30 Expansion Tank is widely used in closed-loop hydronic heating systems, hot water boiler systems, radiant floor heating networks, commercial HVAC installations, district heating systems, apartment buildings, schools, hospitals, office buildings, manufacturing facilities, mechanical rooms, heat exchanger systems, and industrial heating applications. The tank absorbs the increased volume of water created during heating cycles, helping maintain stable system pressure, reduce stress on piping components, protect relief valves from nuisance discharge, and extend the service life of boilers, pumps, valves, and associated heating equipment. It is commonly specified in both residential and commercial heating systems where reliable thermal expansion control is essential for safe and efficient operation.

Technical Specifications:

• Manufacturer Part Number (MPN): 0066606
• Brand: Watts
• Model: ETX-30
• Product Type: Pressurized Expansion Tank
• Series: ETX
• Tank Volume: 4.5 Gallons
• Acceptance Volume: 2.5 Gallons at 12 PSI
• Connection Size: 1/2 in. MNPT
• Connection Type: Male NPT
• Tank Material: Carbon Steel
• Finish: Epoxy Coated
• Diaphragm Material: Butyl Rubber
• Air Precharge: 12 PSI
• Maximum Working Pressure: 75 PSI
• Maximum Operating Temperature: 220°F (104°C)
• Mounting Type: Pipe Mounted
• Orientation: Vertical or Horizontal
• Service Media: Non-Potable Water
• Application: Closed-Loop Hydronic Heating Systems
• Function: Thermal Expansion Control and System Pressure Stabilization
• Charging Valve: Standard Tire Valve Type
• Suitable For: Residential and Commercial Heating Systems

Common Replacements:

• Watts ETSX-30 Free-Standing Expansion Tank
• Amtrol Extrol No. 30 Expansion Tank
• Bell & Gossett HFT-30 Expansion Tank