How to flush a Moen Positrol shower valve?

Before I close up the shower and start on the tile work, I want to flush the lines leading to the valves to flush out the little globs of dirt, cement, etc., that accumulated in the CPVC pipes during assembly. Is there an easy way, or do I just remove the cartridge and have my trusty assistant hold a bucket up to the valve while I go turn on the water?

Hold the bucket and let'er rip. If you have a tub you don't need the bucket.

Mikey said:

Is there an easy way, or do I just remove the cartridge and have my trusty assistant hold a bucket up to the valve while I go turn on the water?

Click to expand...

That's the way I would do it.

It's a new double shower; no tub. Let 'r rip it is. Thanks, guys.

No muss, no fuss...

I was cleaning out the garage and found a 5' length of bilge-pump hose with a 1 1/4" i.d. That fit nicely around the valve body, so with a worm clamp to make me feel better about it, I fastened it on, stuck the other end down the drainpipe and let 'r rip. That will also work after the tile is up, I think.