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Wrench Flats

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Alan (California Radiant) Forbes
Alan (California Radiant) Forbes Member Posts: 4,841
in THE MAIN WALL

I love Caleffi products and these pressure reducing valves are great, but would like to see some wrench flats to help with installation.

0-22.jpg
8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

Two btu per sq ft for degree difference for a slab
STEAM DOCTORIntplm.

Comments

  • hot_rod
    hot_rod Member Posts: 28,108

    good point!

    A 10" cresent grabs well in below the gauge port.

    Screenshot 2026-07-14 at 8.49.34 AM.png
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    pumpcontrolguy
  • mattmia2
    mattmia2 Member Posts: 17,919

    were these designed to be machined for something else in european markets where you didn't need to grab them with a wrench?

  • HydronicMike
    HydronicMike Member Posts: 411

    This is one of the 2 wrenches I use for stuff like this. Wide-thin jaws.

    IMG_0130.jpeg
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 12,675

    I have the complete set of those wrenches in both SAE and Metric sizes. Great for all types of work.

    Screenshot 2026-07-14 at 12.49.02 PM.png

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    ratiorick in AlaskapumpcontrolguyIntplm.
  • Alan (California Radiant) Forbes
    Alan (California Radiant) Forbes Member Posts: 4,841
    https://forum.heatinghelp.com/discussion/comment/1900001#Comment_1900001

    That option comes out of necessity. Flats give you more wrench positioning options.

    It's really not a big deal. I just needed to b*itch about something.

    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    HVACNUTGGrossrick in Alaska
  • Steve Minnich
    Steve Minnich Member Posts: 2,961

    Flats on flats if at all possible. I hate seeing a chewed up component.

    Steve Minnich
    Mad Dog_2
  • jumper
    jumper Member Posts: 2,604

    Decades ago I saw a set of thin stubby wrenches with convex faces. I think at Northern Tool. Never saw them again. I regret that I didn't buy them.

  • mattmia2
    mattmia2 Member Posts: 17,919

    the convex faces are gearwrench. not sure about a stubby version.

  • 109A_5
    109A_5 Member Posts: 4,346

    @jumper, Convex faces ? Are you referring to where the box wrench (and sockets) contacts the fastener ? If so I believe Snap-On Tools called it Flank Drive and they had the original patent on it. When the patent ran out many other tool companies copied the technique.

    image.png image.png
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • hot_rod
    hot_rod Member Posts: 28,108
    IMG_1581.jpeg
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • jumper
    jumper Member Posts: 2,604

    I think so. If wrench applies force to faces rather than corners then fit can be less precise?

  • mattmia2
    mattmia2 Member Posts: 17,919

    there is more material behind the face vs the corners. you can apply a lot more force to the face before it deforms vs to the corner before it shears off.

  • 109A_5
    109A_5 Member Posts: 4,346

    @jumper Less precise ? I suppose it is all in the way you looked at. Maybe less precise in the conventional 6 or 12 point way. However it may be more precise in other ways to make the Flank Drive work correctly.

    How about Flank Drive Plus for open end wrenches.

    image.png
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • ratio
    ratio Member Posts: 4,297

    The first time I saw one of those open ends, I thought "Man, they really let QA go to $h!t."

    I'm still not convinced that the open ends are any better. I think it's possible for the sockets & box ends to actually be better, but I've yet to come across a place where I looked at it & said "Yup, shouldda used something that grabbed the flats."

  • mattmia2
    mattmia2 Member Posts: 17,919
    https://forum.heatinghelp.com/discussion/comment/1901634#Comment_1901634

    it lets the sides of the open end bend more before they lose grip. it also might move the fre to a point where it bends the sides less.

    the big problem here is that rusty fasteners are no longer the size they were when they left the factory.

  • jumper
    jumper Member Posts: 2,604

    I was talking about open end. Occasionally we come across a big (over 1") whatever in a tight spot. That's why I regret not buying those stubby thin wrenches with funny jaws.

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