August 12, 2015

Is there a difference between a buffer tank and a storage tank?

Is there a difference between a buffer tank and a storage tank?

Are they the same thing? What's different?

Really a tank is a tank. Anytime we use a tank for storage of hot or cold water it could be a buffer, storage or both. We usually think of a buffer tank as one that stores thermal mass (sort of like a "flywheel") so a heating or cooling source doesn't cycle too much when smaller loads are turning on and off.  We would use the term "storage tank" for a project that is generating chilled water during the nighttime when electricity is cheap, then drawing off the cold storage during the day to provide HVAC cooling.

Of course the tank you choose must be built and listed for the application temperature and pressure and must have the correct safety relief valves. Choose a well-insulated tank. Also, large pipe connections are important to minimize pressure drop, especially for two-pipe connection applications. A four-pipe tank also provides the added benefit of hydraulic separation for systems that have primary/secondary pumps.

Caleffi ThermoCon and SolarCon tanks are built exactly for these and many other storage/buffer applications. They are well-insulated and have plenty of large, easy-to-use ports. Check out our NAS200 Series, and contact us with any questions!

Bob "Hot Rod" Rohr

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