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How to Fix a Leaking Packing Nut


What is a Packing Nut?

To prevent major flooding problems in a home, as well as to allow easier work for plumbers during repairs, many water lines have shut-off valves. For example, the pipes under your sinks and toilets should be equipped with valves to stop water flow. It’s important to know where these valves are located so you can stop water in case of a plumbing emergency.

However, the packing nut on a shut-off valve can leak, something you may notice when you turn the handle on and off. The packing nut is the part of the valve that provides a watertight seal around the valve stem, and usually, a leaking shut-off valve is the fault of a problem with the packing nut. Here’s how you can make a simple fix.

Basic Packing Nut Repairs

You’ll need a 4-in-1 screwdriver and an adjustable wrench. Use the appropriate-sized wrench to turn the packing nut one-quarter turn to tighten it. This should usually fix the problem. If it doesn’t, you can replace the washer or the packing nut. You’ll need to shut off the water running to this valve—and that means going further down the line, possibly to the water main for the house. Remove the handle from the stem and then fully loosen the packing nut and remove it. Slide off the washer and put on a new one. Now put the packing nut back in place and tighten it—being careful not to tighten it too much, just make it snug and don’t turn any further. Now reattach the handle, let the water flow again, and turn on the valve to see if the leaking has stopped. Make any further tightening as necessary.

If you can’t fix the packing nut yourself, there may be more serious issues with the shut-off valve that will need professionals. We’re glad to assist with any plumbing repairs you may need, large or small.

Mallick Plumbing & Heating, Inc. provides the highest quality plumbing services in Potomac, MD and nearby areas. Call (301) 804-6759 today to request a service appointment.