Like many others I have no owners softener manual, or idea of what kind of softener is in our house. It was installed in 1978 by a company named Surge Water Systems. I want to replace this softener. Went online and compared pictures and suspect the softener is an Autotrol 155 old style 440 with optional bypass system. All plumbing that was needed to install including bypassing outdoor faucets etc. had been done. Suspect all a person has to do is disconnect the old 155 an install a new softener. But, questions arise about doing this.

Found out that the Autotrol 155/440 has been replaced by the Autotrol 255. Is this the wise way to go replace the old with the new softener? Have heard the Fleck 5600 SXT and or Fleck 2510 SXT would be better. But what is the difference in using the Autotrol orginal installed bypass? Would I need a new bypass to install a Autotrol 255 and or Fleck 5600 and 2510 softener?

Can a person who has never done plumbing like myself attempt this work?

In closing how do you tell which size of copper water pipes are in use? Also, the plumbing hookups from the bypass to the softener how do you tell which size, 3/4 or 1 inch?

Once I can understand the answers to these questions, then on to the water test etc. Can anyone recommend an online dealer that sells Autotrol or Fleck whole water softeners?

Thanks In Advance For Helping me understand about water softeners.