Replacement AHU door handles

[orion242]

Working on a site that many of the door handles on the AHUs are broken. Broken as in the unit at some point saw enough pressure, it simply destroys the door latches. This apparently happens often enough that there are buckets of new handles laying around.

This unit must be a frequent flyer for broken door handles. This door is ~15' AFF making it a pita to access as well. So they came up with another solution.

Little background info. These are fairly large units, ~80k cfm. They are doing SF/RF flow tracking and something is clearly going wrong with it.

AHU Replacement door handle.jpg (2.15 MiB) Viewed 4921 times

[Maxburn]

Looks like you can swing those 90° CW and open the door? I don't see scratches indicating this happens though. Is there a window in it or is that just a hole?

[orion242]

That door opens to the inside of the unit. The threaded rod that is holding the door, runs through the two holes the door handles use to occupy. They bend the latches under the pressure and just rip the doors one way or the other. This little guy is prob smashed up on the inside of the door since it swings in. All the doors under positive pressure open in, negative pressure open out. The doors between the SF & RF seem to be the issue. Those could be under negative or positive pressure depending on what nonsense is going on with the fans.

The exterior unit walls are pretty sought. The internal walls between sections and filter racks, damper walls, etc are a bit less tolerant. I'll have to get pictures of the handles. They have buckets of replacement handles onsite. It would take a raging 300# ape to break one, so it must be quite the show when the unit rips the door in or out.