Newbie here, so feel free to move this if it is the wrong spot.
I just got a new compressor about a month ago and until last week I had trouble finding the leak. I finally took a look at the horns (4 horn Siege Engineering) and found a that air was leaking out of one horn. Seemed odd that it was leaking only out of one horn and not the others. So I opened up the valve and cleaned off most of the rust inside.
I put everything back together and it seemed like it worked. For some reason though, it seems like I only loose pressure at night. I fill the tank up all the way in the morning (145psi) then its at that same pressure by 8pm. By the next morning its at 60psi. And if I let it sit without refilling the tank, it will drop to 20 psi by the next day and will stay at 20 psi for a few more days.
Btw, im in SoCal where the weather is at about 80F during the day and about 45-50F at night.
Is there any warranty on Siege Engineering solenoid valves? And yes I checked for leaks everywhere else.