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The Watts 0066606 Expansion Tank is designed for residential and commercial hydronic heating systems. This 4.5-gallon tank manages thermal expansion and maintains system pressure. Its pre-pressurized steel structure and butyl diaphragm ensure long-lasting performance.
This expansion tank is ideal for closed-loop hydronic heating systems. It prevents water from contacting air, enhancing system longevity.
We pulled together the parts most installs need for this unit, plus a few add-ons worth a look. Check what you need — nothing here blocks checkout.
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