TXV's are designed for specific refrigerant use (in your case R-22 or R410A),size tonage/BTU capacity, bleed or non bleed style,etc. Many people consider a TXV a mystery because they have never taken a class or studied its application capability.
Below is a short list of publications for your consumption. Happy reading
http://www.parker.com/portal/site/PARKER/menuitem.734d2913eb3c11da13576f849420d1ca/?vgnextoid=d195f87357e28110VgnVCM10000048021dacRCRD&vgnextfmt=default&division=528d84aa40701110VgnVCM10000048021dacRCRD&literaturetype=Technical%20/%20Service&searchAttr=searchResult&languages=EN&parentCh=Division#results (http://www.parker.com/portal/site/PARKER/menuitem.734d2913eb3c11da13576f849420d1ca/?vgnextoid=d195f87357e28110VgnVCM10000048021dacRCRD&vgnextfmt=default&division=528d84aa40701110VgnVCM10000048021dacRCRD&literaturetype=Technical%20/%20Service&searchAttr=searchResult&languages=EN&parentCh=Division#results)