ceilinglightingtroubleshooting
My house has an old fluorescent ceiling fixture in the kitchen that probably dates back to a remodel done in the 1980s. The bulbs have gone out and I am having trouble figuring out how to open the fixture to replace the bulbs.
The frame is metal and the three individual light panels are plastic
Any suggestions would be appreciated.
These type of boxes usually have 1 or 2 screws going through the bottom into a steel bar that spans between ceiling joists.
I think you are correct that this box is not properly supported.
If you have access from above, you can put a support (2x lumber) across to each joist and then screw through the box into the support.
Options from below only would involve removing the existing box and using one of several replacement boxes. Removing the existing box will involve turning off the power and prying the electrical cable loose from its strain relief. From the looks of the box, it should pull down. Fixture weight will determine which one to use.
The heaviest duty box is one rated for ceiling fans. It uses expandable threaded supports that wedge against the joists side to side. This box would be rated up to 50lbs.
An old work round plastic box has three retractable wings that clamp the box against the drywall. This box is suitable for lighter fixtures, perhaps up to 10lbs. It is very dependant on intact and unbroken drywall for best performance.
Take the photo to several lighting fixture stores and ask. The staff will often have wide knowledge of back catalog.
Best Answer
It is bit difficult to tell from the picture.
Often on those older florescent fixtures the plastic panels have a integral plastic flange on their top edge that supports them- they basically hang inside the metal frame. So they drop in from the top- inside the fixture. To remove them lift up on the plastic and carefully flex and rotate them to get them out. If your fixture is real old then the plastic may have become more brittle and care should be taken not to damage them.