I have read previous post with the identical problem, with no real outcome. Low lube level comes up about every 19 minutes 40 seconds. I checked float on reservoir tank. It appears to be functioning properly, when it's down it opens the circuit, when it's up the circuit is closed and we have continuity. Next was the pressure switch. Ordered a new one and since there is no guage to indicate how much pressure is in the system, I installed a guage to check it. Comes up every 8 minutes, rises pressure to around 24, remains there for a few minutes, then drops of slowly. There is no immediate drop after it gets to 24 until about 5 minutes. Installed new switch, same alarm in 19 m 40 s. What the heck. Mess with the air pressure, it was at 72-73, set it to 80. Viola, no more alarm. Fast forward 5 weeks. Get low lube level alarm, but it's low. Add oil, everything is OK. A few hours later, low lube level alarm, for no reason.
Very frustrating.
Very frustrating.