User Manual
Series ETA
ASME
Pressurized Expansion Tanks for
Heating and Cooling Systems
Models ETA 15 to ETA 240
Watts Model ETA Tanks are ASME fixed bladder type pre-
charged expansion tanks. They are designed to absorb the
expansion forces and control the pressure in heating &
cooling systems. The water is contained in the heavy duty
bladder preventing tank corrosion and waterlogging problems.
FEATURES
• ASME Section VIII Construction
• Heavy Duty Butyl Bladder
• Precharged to 12 psi (Field Adjustable)
CONSTRUCTION
Shell: Carbon steel
Bladder: Heavy duty butyl
Prime painted exterior
PRESSURE - TEMPERATURE
Maximum Design Pressure:
ETA 15 through ETA 60: 150 psi (10 bars)
ETA 80 through ETA 240: 125 psi (8.5 bars)
Precharged to 12 psi (83 kPa)
Maximum Design Temperature: 240°F (115°C)
SPECIFICATIONS
Furnish and install as shown on plans a Watts Model ETA
____ gallon ____ " diameter x ____" (high) pre-charged
steel expansion tank with a fixed butyl bladder. The tank
shall have a top NPT system connection and a .302" - 32
charging valve connection (standard tire valve) to facilitate
the on-site charging of the tank to meet system require-
ments. The tank must be constructed in accordance with
Section VIII of the ASME Boiler and Pressure Vessel Code.
For Heating and Cooling Systems
Job Name Contractor
Job Location Approval
Engineer Contractor’s P.O. No.
Approval Representative
ES-ETA
Watts product specifications in U.S. customary units and metric are ap-
proximate and are provided for reference only. For precise measurements,
please contact Watts Technical Service. Watts reserves the right to change
or modify product design, construction, specifications, or materials with-
out prior notice and without incurring any obligation to make such changes
and modifications on Watts products previously or subsequently sold.
USA: 815 Chestnut Street, North Andover, MA 01845-6098
Canada: 5435 North Service Road, Burlington, Ontario L7L 5H7
Tank Acceptance
Model Volume Volume
Number Gallons Gallons Tagging Information Quantity
ETA 15 7.8 2.5
ETA 20 10.9 2.5
ETA 40 25 10
ETA 60 35 10
ETA 80 45 21
ETA 100 60 21
ETA 120 70 48
ETA 144 80 48
ETA 180 90 48
ETA 200 115 48
ETA 240 140 52
Schedule