Its good to ask questions and seek advice, i wish i`d had someone to ask.. it would`ve saved me a lot of trial and error and dead ends 
You need a pressure switch to sense the pressure in the line from the pump to solenoid with the accumulator tee`d off the line. Something like this one from mercoid (dwyer) looks like a good choice, http://news.thomasnet.com/fullstory/499877
Hp aero components aren`t that expensive as you can see by the $19 price tag, the trick is knowing what to buy
Heres a link to the PS pdf, model #CXA-S3 (NC) 35-150psi range with a 30-40psi deadband or possibly the CXA-S2 if you want a tighter 20psi deadband.
http://www.dwyer-inst.com/PDF_files/CXA_cat.pdf
A cycle timer and solenoid wont cost anything close to $259, don`t buy it from the BC site, i`ll bet that one uses a cheap vibratory coffee machine pump

You need a pressure switch to sense the pressure in the line from the pump to solenoid with the accumulator tee`d off the line. Something like this one from mercoid (dwyer) looks like a good choice, http://news.thomasnet.com/fullstory/499877
Hp aero components aren`t that expensive as you can see by the $19 price tag, the trick is knowing what to buy

Heres a link to the PS pdf, model #CXA-S3 (NC) 35-150psi range with a 30-40psi deadband or possibly the CXA-S2 if you want a tighter 20psi deadband.
http://www.dwyer-inst.com/PDF_files/CXA_cat.pdf
A cycle timer and solenoid wont cost anything close to $259, don`t buy it from the BC site, i`ll bet that one uses a cheap vibratory coffee machine pump
