How To Repair Moen Shower Faucet

A mutual upshot with older Moen shower faucets is only common cold, or only hot water coming out of the faucet or shower caput.  This often happens with showers that are not used very oft, or where the h2o supply is particularly hard or has high levels of contaminants.  If you search the web for aid, the well-nigh often propose is to replace the main cartridge (part number Moen 1225 or 1200).  Notwithstanding, this is well-nigh likely not the source of the issue.

If you remove the shower faucet knob, and remove the cover backside it, you should see something similar the image below.  This is a Moentrol 3570 valve, there are other similar model numbers.

Within the valve is what is called a balancing spool.  This balancing spool valve contains a piston which moves back and along maintaining a given temperature fifty-fifty if the force per unit area on the common cold side is reduced, for example someone flushes a toilet when the shower is in use.  It prevents a sudden blast of hot water which can lead to burns.  When y'all suddenly experience only the cold or hot water flowing regardless of where you lot fix the flow handle, this valve is almost always the culprit.

The piston which is inside the balancing spool will get stuck in one position or the other.  When this happens, it essentially shuts off flow to either the hot or common cold side.  Poor water quality and historic period will somewhen cause the piston to get stuck in its bore.   The balancing spool (function number Moen 1423) can exist seen clearly in the photo beneath.

The first footstep in repairing the balancing spool valve is to remove information technology.  You will demand to use a VERY big screw driver to unscrew the valve (number 2 higher up).  Make certain you shut off your water commencement!  Y'all tin can also utilise a straight-edge piece of metal clamped in vice grips if y'all do non have a large enough spiral driver.  Spray the exterior of the screw with Liquid Wrench or other penetrating oil in advance of your try, it tin be difficult to loosen.  If y'all are lucky, the valve will come out with the screw.  Merely, most likely the summit of the spool will separate, like in the photo below.

If this happens, you will need to retrieve the stuck piece.  The way that I accomplished this was to soak information technology in Liquid Wrench for an hour before my attempt.  I inserted a screw driver down into the piston and tried to lever it out, tapping with a hammer at the same time.  I then bent a slice of metal rod into a hook shape and fished it within and caught it against ane of the holes in the torso of the spool.  Using a pair of vice grips I pulled until it came loose.  This may take some piece of work, so exist patient.

One time removed you have 2 options, supervene upon with a new one, which is not inexpensive, retail price is between $55-95.00.  Or, you can usually successfully clean the spool.  To do this, remove the round slice of metallic at the dorsum of the valve (seen above).  Just sideslip a modest screw driver into the gap and twist it out.  And so tap the piston out of the bore.  I used a socket to support the back of the spool, and used a hammer and screw driver to tap it out.

Next, y'all want to use fine sandpaper to clean off the piston journals, and the inside of the bore of the valve.  Go aggressive, you want the bore and journals to be polished clean.  Work the piston dorsum and forth in the bore until there is absolutely no sticking or binding.  Then utilise plumbers grease and reassemble.  Plough the water dorsum on and test the faucet, you should now accept hot and cold water, and just saved yourself a couple hundred dollar repair bill.

Source: https://www.z-car.com/blog/repair/moen-shower-faucet-provides-no-cold-water-only-hot

Posted by: keithberch1963.blogspot.com

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