Vacuum notes

Purchased a few air valves off ebay but they require pressure to operate.. and dont work with a vacuum.

So.. a bunch of solid state relays and some fish tank air pumps which I modified to run in reverse, ie suck instead push..

HAILEA ACO-9903:  specs at 4lph and we are using 1 of 2 channels so 2lph..

Easily modified but not always sucessful..

 

Also, 1 solid state relay wont turn off the pump fully (Inductive laod?) but 2 in series does.. a bit crude but a solution for now..