Mark2line,
Here is a post I made earlier on the same topic-
"skoob, you might look at
www.viega.net/4693.html . If your unit looks like these, they sell a replacement for about $90.00 delivered by UPS. I am getting ready to install my second one. They do crack when they freeze

. Be sure to get the right size. On my first one had to return a 1/2" one for the 5/8". Sales office in Wichita, KS 800-976-9819 I think. Very helpful cust svc folks."
Look back to 5-27-09 for the full thread discussion.
Hope this helps.