What's New?
The reliable 521 Series Adjustable Thermostatic Mixing Valve is now available with a removable mixed outlet temperature gage, either as a complete assembly, part number 521519A, or as an adapter, NA10056, with a threaded 3/4" sweat union to field replace the existing outlet fittings on other 521 series models.
 
This additional configuration comes out in response to good ideas from our customers.  This option speeds up the temperature setting process by providing an approximation of the temperature at the point of distribution installation, saving the time to check delivery temperature a distance away.  More important, however, the key benefit for the addition of a temperature gage is to have dedicated "proof of temperature" verification, of which more and more inspectors are expecting to see.  The 688003A manifold temperature gage has a ±6°F accuracy and 5 minutes ±2 minutes response time, so it may have some limitations depending on the installation.  Please note:  Do not use with point-of-use distribution mixing valves where scald protection is required.

 
The Caleffi Advantage!
Caleffi Thermostatic Mixing Valves for radiant mixing or point of distribution potable water applications come in 1/2", 3/4" and 1" sweat and NPT sizes, for 80°F to 150°F temperature settings with a locking set point knob.  The 521 Series Mixing Valves are made with dezincification resistant body and internal anti-scale materials to prevent mineral build-up.  These mixing valves are designed to prevent the flow of water from the mixed water outlet in the event of the failure of hot or cold water supply and specifically certified to ASSE standards.
 
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