ANOTHERFLAP OPERATOR: just a quick correction to your last writing if you dont mind?
the pack valves are a simple on/off valve and nothing to do with temperature control - the temp control valve however funnily enough controls the temperature it is however very easy to replace...the pack valve is a different story and can take upto about 4 - 5 hours. depending on the mod status of the pack valve it is a very simple process to replace the pack valve filters but if its an older unit lets say it can "be fun!"
