Is there a way to adjust the tension on a stem for a posti-temp valve? I've taken off the handle and trim, and I don't see any way to adjust the tension.
I have a single turn handle on my bath tub. It is a posi-temp valve. The handle is difficult to turn, and I have broken a couple of the plastic handles already. I'm considering buying a metal handle. However, the plastic handles should have lasted longer, and it makes me believe the stem on the valve is too difficult to turn.
The stem you speak of is actually connected to the internal cartridge. I believe it may have been over tightened when installed, or it was leaking a bit and some gorilla cranked it down. You will need to remove the bezel trim, and loosen the nut that holds the shaft and cartridge. There may be two nuts. If you loosen too much, the valve will leak. Some models require a spanner type wrench to loosen. A good close up pic without the trim would help here. If you can post the exact model number, we may be able to pull up an install detail for ya.
After breaking another handle, I found the instructions for installing a posi-temp valve. It did not mention any nuts as suggested in this answer.
I called Moen support at the number listed in the installation instructions. They informed me that the tension on a posi-temp handle cannot be adjusted. From my description of having to re-grip the handle multiple times to fully open the valve, they suggested replacing the posi-temp cartridge (Moen part 1222). They said hard water and some cleaning solutions can build up around the cartridge and make the stem difficult to turn. I installed a new cartridge and handle, which was simple enough, and now the handle turns much easier!
I also found a helpful video on replacing a posit-temp cartridge. This video mentions a special tool to remove the cartridge. I was able to replace my cartridge using only the plastic tool included with the new cartridge.
Kudos to Moen for investing in quality phone support. The first person I was quickly connected to answered all my questions confidently as if they had years of experience with these products instead of reading from a support script.
I have had the opposite problem, which I understand from at least one plumber is not that uncommon. My VOSS style handle on the tub faucet 'flops' because the internal cartridge mechanism wasn't redesigned to adequately support the weight of the newer decorative handles. The 'push-pull' 'on-off' function works, but when the handle is rotated to adjust the temperature, the handle 'flops' back into a default position of the handle pointing down vertically. Moen sent a new cartridge and handle but somehow some part of that was not appropriate either. The contractor installing the faucets has suggested that the problem will fix itself overtime--apparently via the build up of 'crud' as described above, but I don't view that as a suitable fix. Am pretty 'p.o.'d', as I coordinated all of the fixtures/accessories to that style group in the context of a rather expensive bathroom remodel and feel that someone should have warned me or that there should be a 'real' and acceptable 'fix'.
We have the same Moen Cartriges in our house. A new cartridge had lubricated o-rings which is what causes them to work so easily vs. the old faucets where the lubrication has worn off and they are hard to turn and push in and pull out. Guess you could pull out the cartridge and wipe off all the lubrication for the o rings...and well make it act like an old one, complete with failing O-rings. Would be nice if after market manufacturers did their homework and balanced the lopsided newer fancy handles. Maybe some lead weight on the inside hub could help.
