Hot and cold backwards on a moen shower faucet

remove and turn cartridge 180 degrees then re-install

Easy one.
Feel the pipes. The pipe on the right should be cold. If the pipes are correct, turn the cartridge 180 degrees.

u need to adjust the scald protector all single handle units are shipped in cold position for safety reasons if have paper work for handle it explains how to adjust if not unscrew handle and remove on handle / valve stem will see a red and a blue plastic clips pull back clips and turn slightly and push back do this till desired hot and cold setting are to your liking replace handle and your done

Pull off the handle and there are limiters located under it. They come set with not enough hot allowed, I have found. It is an anti scalding issue.

If this is a Moen posi temp valve you may need to adjust the temperature limit stop. It is located under the handle. Usualy a plastic peice with grooves in it so it fits in another peice in the valve. If I remember right you pull this peice out and turn it counter clockwise to get more hot water. Do this in small increments and reassemble and test. I hope this helps.

these valves can be adjusted by removing the handle and adjusting the white gear that regulates the hot and cold that come out, try going more to one way if it gets colder then go the other way.

You can try to rotate the first plastic ring to the left of center a few teeth, this will let the handle advance alittle more to the hot side.

Single or dual lever? A new ball if single lever. Home Depot or Menards will carry them. Teflon tape if dual cartridge. Stay away from moving parts

Did the hot water shut off get turned back on fully after the change? Is the hot water line kinked under the sink? Is the hot water shut off valve working?

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take out the cartridge and flip it over.