Over the weekend I visited a local high school for a swim meet.  Right away I noticed MANY pairs of fire doors equipped with LCN Sentronics, which are designed to hold the doors open until the fire alarm sounds and then close the doors to deter the spread of smoke and flames.  Some of these doors were propped open with wood wedges (uh-oh).  When I took a closer look, I realized what the problem was.

The units installed in the school, on cross-corridor and stair doors, were LCN 4310ME-SF multi-point hold-open units with a swing free arm.  (If your eyes are starting to glaze over at the mere mention of hardware model numbers, stick with me.)  These units will hold the doors open at any degree of opening, which is why some of the doors have wedges – to keep the doors from standing open at odd angles.  This unit is more suited for a fire-rated hospital patient room (this application was once very common), so the staff can leave the door partially open.  After the door is opened for the first time, it feels like there is no door closer – the door swings freely.  Great for a hospital patient room – not so great for a high school.  The doors are standing open at all angles, swinging freely, and when someone goes through the door there is no resistance at all so the doors are getting a fair amount of abuse.

My first choice for almost all of the cross-corridor and stair doors in this school (basically any school) would be wall-mounted magnetic holders.  If I absolutely had to go to a closer/holder unit, I would use a single-point hold-open rather than a multi-point.  This would avoid the problems of the doors standing open at random angles, and the lack of resistance if someone goes through a closed door.  At this point I will recommend that they reinstall the arm screw so that it is no longer a swing free arm.  At least that should keep the doors standing open in the right position.  If you have any other ideas, please leave a comment.

If that explanation doesn’t make sense, just leave me a comment and I’ll elaborate.  Here are some photos, as well as a video of what happens when someone walks through a door with this unit on it…

Stair Pair


Here you can see the two pieces of the arm…the arm on the left, and the swing free portion at the end of the arm.  This piece stays in the fully-open position until the fire alarm releases it.  It then rotates around and picks up the rest of the arm in whatever position it is in, and closes the door.  The screw that I will recommend reinstalling goes in the two screw holes shown here, to reconnect the arm to the swing free portion.

Swing Free Arm

This pair is not fire-rated, but I’m guessing it is to prevent a dead-end corridor.  Note the wood wedges.

Dead End Corridor

Here’s the video…this was normal use, and you can see how the door operates:

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