Tell that to the gentleman who was asking for help because his pump was making funny noises he even posted a vid link for it. My reply #9656
got it cleared up. It is an issue. Probably more so than some people realize.
Also say you do have yours set up fittings at the top. As you said the air only has one place to be right? If there is a significant amount of air for expansion purposes then it's all trapped in the area of the fittings. That means that you don't even need to move the system to have air get into the return line. It's right there. Power fluctuates enough that all it would take is a large enough surge to make the system hiccup and there you have it, air reintroduced to the line.
Now what are the chances of this happening if the fittings are strictly in the down position in a vertical mounting? ZERO there is ZERO chance of the air getting introduced to the line. Even if you move your system, unless your cable management skills demand an upside down orientation which is pretty doubtful in itself.
What you consider over thinking, I consider solid planning. If I have a working plan to implement before I even mount one (I did) then I can avoid the issues altogether. Look in my sig My 932 YouTube link. System is 100% horizontal all the air is trapped at the top and no chance it gets back to the pump.
Originally Posted by looser101
Really you guys are over thinking this. If air was an issue you would hear it making noise going through the pump, like it does sometimes if you move your case when it's running. If it's not making any noise then the air is sitting somewhere out of the flow of the liquid. Proclaiming that it has to be in a certain direction is just...well...silly.