Apply heat to the stuck fixture or.
Delta sink faucet bonnet nut stuck.
Removing a stuck on bonnet nut when changing a cartridge on the delta shower valve.
Here are some nut freeing tricks from richard trethewey.
Make sure that the surrounding area is free of any valuable items as the action to strike the motion against the plumbing nut.
Remove the faucet s bonnet nut.
If the fixture or nut hasn t loosened go to step 2.
Any time you replace an old faucet you have to take off the locking nut that holds the faucet tight to the countertop.
The bonnet nut fits over the faucet valve and holds the valve into place.
The stroke by billy squier permission to use in this video by the legend hims.
But often that nut will be frozen due to corrosion or mineral buildup from years of water seepage.
The easy way to access a corroded basin faucet fixing nut for removal.
To remove a stuck faucet nut you need a wrench or locking pliers to break the mineral deposits grip and then turn in the opposite direction.