Apprentice question
Field check
Standard work. Do it right, keep moving.
A soft aluminum filter grille frame can twist if the clips are over-tightened. Loosen, square/shim the frame, then snug it without distorting the door opening.
['Return filter grilles and ceiling filter louvers need a square frame so the hinged face can swing open. If the subframe is out of level and the clips are cranked down, the aluminum housing can rack.', 'Back off the clips, square the frame, shim the opening if needed, and retighten gently. Verify the door opens, closes, and latches before ceiling tile or finish work continues.']
More in Equipment Connections: RTU, AHU, VAV, Fans & Louvers