A Moen kitchen faucet that drips from the spout has a worn cartridge. The cartridge is the same Moen 1225 or 1255 Duralast cartridge used in many Moen bathroom and tub faucets, so the repair principle is identical. The difference is access. The cartridge in a kitchen faucet is under the handle, which is in the middle of the sink where you can see what you are doing. The job takes 20 to 30 minutes and costs $0 because Moen ships a free replacement cartridge under their lifetime warranty.
If the leak is from the base of the spout where it meets the faucet body, the O-rings on the spout have worn out. If the leak is from the pull-out spray head when the faucet is running, the spray head or the hose connection needs attention. Here is how to fix each type of leak.
Leak From the Spout: Replace the Cartridge
A Moen single-handle kitchen faucet uses a 1225 or 1255 cartridge. The 1225 is the older brass cartridge. The 1255 is the newer Duralast plastic cartridge. They are interchangeable in most Moen kitchen faucets. The cartridge controls both water flow and temperature. When the internal seals wear out, water seeps past the closed cartridge and drips from the spout.
Shut off the water. The shutoff valves are under the sink. Turn both hot and cold valves clockwise until they stop. Open the faucet to release pressure. If the valves under the sink are stuck or will not fully shut off, turn off the main water supply.
Remove the handle. On most Moen kitchen faucets, the handle is attached by a set screw on the underside or the back of the handle base. The set screw requires a 1/8-inch or 3/32-inch Allen wrench. Loosen the set screw and lift the handle off. If the handle is held by a decorative cap on the top, pry off the cap with a flathead screwdriver. Under the cap is a Phillips screw. Remove it and lift the handle off.
The cartridge retainer clip is a U-shaped brass clip that slides into the top of the faucet body. Grip it with needle-nose pliers and pull it straight up. Keep a finger over the clip. It is small and will launch if you lose your grip. The cartridge is now exposed. Grip the cartridge stem with pliers and pull it straight out. Do not twist or rock the cartridge. A stuck cartridge can be freed with a Moen cartridge puller, which costs $15 to $20 and threads onto the stem to pull the cartridge out mechanically. If you do not have a puller, grip the stem firmly and pull steadily. It will come out.
Inspect the inside of the faucet body with a flashlight. Moen cartridges do not have separate springs and seats like Delta cartridges. The seals are built into the cartridge. If there is debris, scale, or mineral buildup inside the faucet body, clean it with a cloth or a small brush. The new cartridge will not seal against a dirty valve body.
Coat the O-rings on the new cartridge with plumber’s silicone grease. Slide the cartridge into the faucet body. The cartridge has a notch that aligns with a tab in the valve body. The notch must engage the tab. The cartridge will slide in fully when it is aligned correctly. Do not force it. Reinstall the retainer clip. It should snap into place. The clip holds the cartridge in position against water pressure. If the clip is not fully seated, the cartridge will push out when the water is turned on.
Reinstall the handle. Tighten the set screw. Turn the water back on slowly. Test the handle through the full range of motion. Check for leaks at the handle base. If the handle is difficult to move or the temperature range is reversed, the cartridge may be installed backward. Remove the handle, pull the cartridge, rotate it 180 degrees, and reinstall.
How to Get a Free Moen Cartridge
Moen’s lifetime warranty covers the cartridge. Call Moen customer service or submit a request on their website. You will need the faucet model number, which is typically on a label attached to the cold water supply line under the sink or on the original packaging. If the model number is not available, describe the faucet to the customer service representative, who can identify it from your description or from a photo. Moen ships a replacement cartridge at no charge. Shipping takes one to two weeks. If you need the faucet working today, buy the cartridge at a home center for $15 to $30 and keep the free one as a spare.
Leak From the Base of the Spout: Replace the O-Rings
Water that drips from the base of the spout where it swivels, or a spout that is difficult to turn, means the spout O-rings have worn out. The spout O-rings are separate from the cartridge. Replacing the cartridge will not fix a spout base leak.
Shut off the water. Remove the handle and the cartridge as described above. The spout lifts straight up and off the faucet body. It may require a firm upward pull. The spout is held in place by the O-rings, not by fasteners. Under the spout are two or three black O-rings seated in grooves on the faucet body. Remove the old O-rings with a pick or a small flathead screwdriver. Coat the new O-rings with silicone grease and roll them into the grooves. The O-rings are size-specific. Buy a Moen spout O-ring kit for your faucet model. A universal O-ring assortment from the hardware store may not contain the exact size. The correct O-rings are included in Moen repair kits or available from Moen directly.
Slide the spout back onto the faucet body. Reinstall the cartridge and the handle. Turn the water back on. The spout should swivel smoothly and should not leak at the base.
Leak From the Pull-Out or Pull-Down Spray Head
A leak from the spray head when the faucet is running, or a spray head that drips when the faucet is off, has one of three causes.
The spray head connection is loose. Unscrew the spray head from the hose. Wrap the hose threads with Teflon tape, two to three turns clockwise. Screw the spray head back on and hand-tighten. Hold the hose while tightening the spray head. Do not let the hose twist, which can damage the internal tubing.
The diverter inside the spray head is clogged or worn. Moen spray heads contain a small diverter valve that switches water between the stream and spray modes. The diverter can become clogged with mineral deposits. Soak the spray head in white vinegar for 30 minutes to dissolve mineral buildup. Rinse thoroughly. If soaking does not fix the spray pattern or the leak, replace the spray head. Moen sells replacement spray heads for their current faucet models. A replacement spray head costs $20 to $40.
The hose has a leak. Inspect the braided hose for kinks, cracks, or bulges. A leaking hose must be replaced. The hose connects to the faucet body under the sink. The connection is typically a quick-connect fitting or a threaded nut. Disconnect the old hose. Attach the new hose by pushing the quick-connect fitting until it clicks or by threading the nut and hand-tightening. Moen replacement hoses cost $20 to $35.
Side Sprayer Leak: Replace the Sprayer or the Diverter
If your Moen kitchen faucet has a separate side sprayer that leaks or drips, the sprayer head is the most common cause. A side sprayer that drips from the nozzle when the faucet is running means the internal valve in the sprayer head is not closing completely. Replace the sprayer head. It unscrews from the hose and a replacement costs $15 to $25. A side sprayer that leaks only when the sprayer is activated, or a sprayer that does not switch between stream and spray, is also a failed sprayer head.
If the sprayer has low pressure or does not work at all while the main faucet works normally, the diverter valve inside the faucet body is the problem. The diverter is a small plastic or brass valve that redirects water from the main spout to the side sprayer when the sprayer trigger is pressed. When the diverter fails, it does not redirect water, or it redirects water constantly and causes the main spout to sputter when the sprayer is not in use.
To replace the diverter, shut off the water. Remove the handle and the cartridge. The diverter is a small plastic piece that sits in a recess in the faucet body below the cartridge. Lift it out with needle-nose pliers. A Moen diverter replacement kit costs $5 to $10. Press the new diverter into the recess. Reinstall the cartridge and the handle.
Frequently Asked Questions
Should I replace my Moen 1225 cartridge with a 1255?
Yes. The 1255 Duralast cartridge is the updated replacement for the older 1225 brass cartridge. It is made of plastic and composite materials that do not corrode, and it includes an improved seal design. Moen recommends the 1255 for all faucets that originally used the 1225. The 1255 is a direct replacement. No modifications are required.
My Moen kitchen faucet handle is stiff and hard to move. Is that the cartridge?
Yes, and it is a warning sign that the cartridge is failing. A stiff handle means the internal seals are hardening or the lubrication is gone. The cartridge will eventually leak. Replace the cartridge now while it is still functioning. The replacement takes the same amount of time whether the faucet is leaking or not.
What if my Moen kitchen faucet has two handles?
Moen two-handle kitchen faucets use individual cartridges for the hot and cold sides. The cartridges are smaller than the single-handle 1225 and are specific to the faucet model. The repair is similar: shut off the water, remove the handle, unscrew the cartridge retaining nut, pull the old cartridge, insert the new one, and reassemble. Moen provides free replacement cartridges for two-handle faucets under the same lifetime warranty.
