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3/4" Caleffi anglemix 520 mixing valve

Rickoo Member Posts: 54
Installing one of the above on an indirect water heater and wondering if there is any documentation on the proper way to install the inlet check valves and associated screen strainers.

The paperwork that came with the mixing valve doesn't address this and thought I'd ask here before installing them. I can clearly see the proper position the checks valves need to be inserted, but not sure about the screens. Once the check is fully inserted, I assume there will be enough clearance for the screen?

The manual warns of test fitting the check valves prior to installation of the mixing valve and if removed once installed, they will be damaged and not seal properly when re-inserted. So, I assume these cannot be removed and cleaned/serviced?

Here's a pic of the valve. Any help is appreciated!


  • dko
    dko Member Posts: 611
    edited April 2023
    Check on hot and cold, none on mix outlet. Screen cone pointing opposite the check, there is a slight indentation for the screen on the fitting. Gasket over the screen holds it down when nut is tightened. The orientation you have the check inserted in the photo is correct.

    If this is the only strainer/mesh, this will be what you will check for blockages down the road when you feel like you're losing pressure.

    Check valve is replaceable, strainer is easily removable for cleaning.
  • hot_rod
    hot_rod Member Posts: 22,251
    Do you have a recirc pump?
    The checks are not required, sane with strainers, they can be a maintenance issue
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Rickoo
    Rickoo Member Posts: 54
    Thank you! No recirc present.