This PVC coupler is dripping enough to empty my hot tub in a few weeks. I can't figure out how to remove it. Do I need to cut? Or is there some way to get it off, put new sealing tape, and put it back?
Try a channel lock type pliers on the fitting, front center of the picture. Open the jaws so when you grip the plastic part with the serrated edges you do not squeeze or distort the plastic piece that you are trying to turn. First try to turn this part "down" which will Tighten the joint, just slightly to break the seal, then upwards to un-thread (remove) the fitting. You may have to try this up then down turn several times. If you can remove this "union fitting", you will probably find a gasket seal. You may need a new gasket or you may be able to clean up the old gasket and apply a small amount of RTV silicone to both sides of the gasket. If you do not have the correct tools or think you can not do this yourself ask someone for help or call a hot tub company to do the repair. Sometimes it is cheaper to call a professional. Last thing; I would not cut anything until I have called a professional for advice.