Replaced Moen cartridge 1222B Posi-Temp, now temps all wrong

We just got this cartridge from a well meaning hardware store employee and I don't know that they faucet was Posi-Temp before (wouldn't it say so somewhere??).

Now, when pointing up, faucet is off (good). Turn it to the left, it's all cold (weird). Turn it right, it's really hot (bad) and then turn it further (to say 4 o'clock) to get to comfortably warm. This is a little scary since we have young kids. The faucet doesn't turn around 360.

What went wrong - did we get the wrong cartridge??

Thanks in advance!

Some of those things can be inserted backwards...not sure if this one can. If you take it out, can you rotate it 180-degrees and reinsert it? Wait for somebody that works with these things for more enlightenment.

Fortunately, Moen has only two common cartridge sizes, and you could not physically put the wrong one in.

Remove the handle, rotate the stem 180 degrees, then put the handle back on.

Moen

With the "larger" Positemp cartridge you have to remove it before rotating it 180 degrees.