Thank you for your reply.
Maxim has always created interesting chips, I remember using some of their DTMF chips to create telephone projects back in my history... For this project they will be over kill.
I found a Pressure Transducer at Amazon that is priced ok and fits the pressure range I'm looking for but is not a 1 Wire device. I've already ordered the ADC PCB from the store on this site so I guess I can experiment with it. My concern with doing this is the accuracy after I calibrate the output readings with a handheld guage. Over time if there is any voltage or temperature drift... well I don't want to overpressurize the main hydronic loop but rather kee it between 25-40 PSI.
My Python app will monitor the pressure and if it drops below 25 PSI then will signal a solenoid valve to open until the pressure reaches 40 PSI. Although the main loop does not lose much water, over the past several years it has sprong a leak and that caused my solar array of 8 x 32 evacuated solar tubes to reach an over heating state... they were creating steam and the noise of the copper flexing was the only alert I had. So while I'm upgrading the entire control system to a RPi from an off-the-shelf monitoring system, this is one of the readings I want to start collecting.
Again thanks for the suggestions.