February 19, 2015

About my expansion tank...

Expansion Tanks

We get questions regarding locating and orientation of expansion tanks. Can I mount the tank on its side?  Can I mount it under my dirt separator? Where is the best place to connect it into my hydronic system?

These questions have long answers, too much for a blog, so let me give you some short answers and recommend the book Modern Hydronic Heating by John Siegenthaler. Chapter 12 has everything you want to know about expansion tanks. Also, check out our archived Coffee with Caleffi™ webinar (Aug. 2014) - Expansion Tanks:  Designs, Sizing and Applications.

The tank should be mounted such that the process connection is at the top, so the air bubbles can rise up and out of the water side of the tank. If the tank is on its side, air can get stuck inside and cause corrosion at the steel tank wall. You don't want rust buildup in the tank; it can damage the bladder.

Avoid mounting an expansion tank under a dirt separator; the dirt will get into the bladder area and could cause damage.

Below is a nice diagram from page 3 of our idronics™ journal (Edition 2), showing where to mount and where to not connect the expansion tank. Check out our entire idronics collection for more information.

Questions? Leave us a comment and we’ll reply!

 

 

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