Somebody could tell me which is the procedure for install a extension of 25ft-1/2" polycopper tubing to my propane system?
What are the tools that I need?
1. Shot off the main valve It is Ok... then.
2...
3...
4...
5... Test for leaks... how?
6... Purge the system... How.
7... Finally, where could I locate the Tag. if is it necessary?

Propane is best left to the professionals to properly install. You could happily blow yourself to kingdom come very easily if done wrong. Contact your propane supplier and have them properly install this line. Do you really need your home burnt to the ground?

The leak testers are not available for sale to non professional people. And the cheapie leak testers are not reliable. The professionals can have you up and running in a very short time and you will be safe.

The cost to do this is very reasonable as well. Why monkey around with propane??