Hot Tub Filter Repair and Maintenance page 6

The entire air relief valve itself simply unscrews from the T assembly. Apply Teflon or pipe dope to the new one, and screw it back in place.

The pressure gauge also just threads into the T assembly. If you have a leak there, unscrew the gauge, apply Teflon tape or dope to the threads, and screw it back into place. If the gauge doesn't register or seems to register low, take it out and clean out the hole in the bottom of the gauge. Dirt can clog this small hole, preventing water from getting into the gauge for accurate pressure readings.

For both of these procedures, remember when removing an air relief valve or gauge that you must secure the T with one wrench or pliers while removing the component with the other. The T assembly can easily snap off the filter lid or at the very least come loose if you fail to hold it secure when removing or replacing a valve or gauge. The T assembly itself can come loose and create a leak where the close nipple passes through the hole in the lid. Here you must remove the lid and tighten the nut from the underside of the lid.

Prevention is always the best cure, so examine cartridges, O-rings, and other components carefully each time you break down a filter for cleaning, and always take your time when reassembling. Sloppy reassembly after cleaning is the cause of more leaks than anything else in filters!