I use a low pressure shut off switch on one of my wells. The tank is a Wel_Flo WF60. No water. I checked the air charge and it showed only a couple of pounds of air pressure. No water pressure because the pressure switch did not kick in. I manually started the pump with the pressure switch lever and no water came out of the tank schrader valve with it held open, (pump running). I would have thought if the diaphram was leaking it would allow water on top of the diaphram and leak water out the valve.
Refilled the tank to a air charge of 28# and all seems OK. Could it be I just have a small leak in the valve letting air out? I can bubble test it tomorrow.