Shower faucet leaking

I installed a pressure balancing bath and shower set from American Standard in my recently built walk in shower. This shower does not have a bath so I blocked off the outlet to what would have been the bathtub faucet.

It now leaks sporadically from the shower head. I changed out the cartridge but it is still leaking enough to keep the shower floor damp. I did notice that if I run the bathroom fan there will be a short burst of drips from the shower head. I have placed a pail under the shower head to catch these drips and I can hear them when they hit the bottom of the plastic pail. The drips are not steady like you would have with a leaking pressure valve faucet for example.

I am theorizing here but am wondering if the problem lies in the unit. When one turns off the shower I am thinking that water will remain standing in the pipe running up from the balancing unit to the shower head and that it is this water that is prompted to drip when something shakes the wall [as in the bathroom fan].

If the bathtub faucet were installed, water could have run down this pipe and effectively cleared the lines. Blocked off, the water has nowhere to go and stays in the pipe and drips when disturbed.

Is there any solution to this other than to find a new unit?

I tried to phone American Standard but their voice mail effectively shuts off all communication.

Whaddaya think?

You might find this interesting.
http://www.terrylove.com/forums/showthread.php?49471-american-standard-leaking-shower-cartridge

I happened to find an American Standard item on another style of shower valve and, unlike my particular unit, the information on leaking includes a considerable amount on the balancing unit and its o rings. I will take it apart again tomorrow and see if I can find some new o rings. I didn't install this unit for two or three years after I bought it and it is entirely possible that the o rings dried out.

http://www.americanstandard-us.com/customerservice/warranty/FaucetLifetimeFunctionFinish.aspx
I just read this, not impressed, when you have a problem with moen they just send you the parts as long as you have a model number.

I am trying out the 'swelling' grease first to see if that makes any difference. Otherwise I might be looking for another balancing unit. I partially took it apart and greased all of the o rings but it is now possible I have not put it back together properly. I undid the four small screws with self-contained nuts in an effort to pull it apart completely but did not succeed. Something is still holding the two sides together and I cannot determine what it is so I am just greasing and putting everything back in place. Will see tomorrow if it leaks [and I suspect it will] and if so I will head to Home Depot to order in a balancing unit.

Home Depot said that American Standard does guarantee its stuff but when I went to a local plumbing outlet they charged me $27 for the cartridge.

Yup you can buy parts, for warrentee replacement you have to deal directly. Usually you can find a toll free number on a new product box.