I am trying to install thin LED recessed lights in my hallway. I need to remove the old ceiling box, as shown in the picture. I tried to remove the box for the whole day but was unsuccessful. I cut the drywall around it ad is sure that it is not fixed with a joist or anything.
I removed the punch knockouts and found that the whole ceiling box was connected to three conduits using the connected, as shown in the picture below. The conduit brings in the wire for a three-way switch system to the said ceiling box. There are the big nuts that are tightly screwing these conduit connected at the backside of the box.
Please give any suggestions as to how to remove the box. I still want to use the same wiring so don't want to damage the conduits or wires coming out of them.
Thank you
Best Answer
The existing answers are correct in that you should not, in all likelihood, be attempting to remove this box or the wiring or the conduit.
However, to actually answer the question you asked, since there are occasions to actually remove and replace a box*
The nut that is visible inside the box on the cable clamp/conduit nipple is a standard righty-tighty, lefty-loosey nut. Usually, you thread the nut on to the nipple, tighten it by hand, then place blade an old flat-blade screwdriver against one of the notches sticking up on the nut tap it with a hammer to tighten it down. To loosen it, simply tap in the opposite direction (turn it counter-clockwise). One or two taps should have it loose enough for you to then turn it by hand to back the nut off.
Tap in the direction of the green arrow to tighten and the red arrow to loosen.
Image courtesy of topaz-usa.com. First small image I found for what I was after. Arrows are own work.
Again, unless you are completely removing the circuit, make sure you replace the box when you're done. All wiring connections must be made in an approved box.
*Valid times to remove/replace the box include replacing a light-weight ceiling fixture (mounted to a standard-duty box) with a ceiling fan (mounted to a heavy duty, fan-rated box). Also, when adding a circuit, you may exceed the legal fill for a box, so may choose to replace the box with a larger/deeper one. There are other times, these are just 2 examples.