In article 9584d609-8e16-4cf5-9dbf-5dc41bcedb45
@s8g2000prg.googlegroups.com, alt.home.repair, AGlassman409
@gmail.com says...
In all the post I found about replacing a Moen 1200/1225 single handle
shower cartridge, none of them mentioned that if you put it in upside
down, the hot will be on the right instead of the left.

Yep, amazing. I've done it both times I've installed the things.
The first time I'd replaced the entire mixing valve and thought I'd
crossed the hot and cold pipes.

I could not find anything on the cartridge itself, the instruction
sheet that came with it, or anywhere else that tells you which way it
should go in. I (of course) put mine in upside-down and had to pull it
all out to reverse it.

It's mentioned in the instructions that came with the Moen
cartridge. You didn't have to pull it, just spin it 180 degrees.
The stop is on the knob, so with the knob off it turns all the way
around.

I only hope that this helps someone else avoid my mistake. Or, if
someone how knows about this part could post a reply to tell the rest
of us how to tell which way it up.

Don't care. If it's wrong, just turn it 180. Then put the knob
back on. ;-)

--
Keith