<a href=showthread.php?s=&postid=2332678#post2332678 target=_blank>Originally posted</a> by Vincerama2
Dave, I went back and read your very first post, and now I'm going to share something I discovered last night!
After some fiddling with the plumbing a few days ago, I somehow managed to mess up my EV-120. No matter what I did, the water level would NOT come down! However, I know that I DID have the water down below the platform before and that it WAS skimming well then! Yesterday morning, the water level was way up in the tube part and when I got home, the skimmate was watery and weak and had overflowed into my overflow bucket.
Even with the gate valve WIDE OPEN, the water level would not come down...
This is what happened...I was sick of the glurping of the outlet pipe, which was partially submerged in my sump water, and which I figured was causing the skimmer to work inconsistently because as the skimmer water level changed, the sump level changed and then I'd get a feedback loop on the water level as teh outlet pipe was submerged or not-submerged. So I tried to quiet the outlet. I eventually gave up because I couldn't stop the glurping. I HAD a horizontal run, then a 45 degree bend towards the water and then a small piece of pvc with a few holes in it (to let out the air to prevent glurping) lightly in the 45 bend. I CHANGED it to a straight horizontal run with a T at the end (but with the "long side" of the T running inline with the pipe so that a little air could escape out the single open end that was pointed up (like an invrted letter T). This caused a laminar flow of water that was more tolerable. HOWEVER, that's when my troubles began! I couldn't understand it, now the outlet was a straight shot into a waterfall, NO backpressure at all, and with the gate WIDE OPEN, I couldn't control the level! I messed with the air valve but nothing worked. So I gave up, but decided to work on the outflow problem again, I used a sideways T valve, running downwards into the water, but that caused glurping, despite the "air escape chimney" created by the sideways T (opened at the top)...
Eventually, I got rid of the T altogether and used a 90 degree bend, which went downwards with a short pvc piece connected to a 1" to 2" bushing, which in turn had a 2" coupler on it (like a bell so that the water would go into the bell under water)...
V:eek1: Holy shmokes! I had tried drilling air holes into the 1" to 2" bushing to let the air out but then I tried one without holes. And .... V:eek1: It all worked! No sound! I could adjust my outlet flow again!
Here's what I concluded....in the outlet pipe, I had holes to let air "escape" but what I was really doing was creating venturis to drive more air down the pipe to glurp. OK, so then I got rid of the holes and SUBMERGED the end of the pipe...well guess what, now I have a siphon that DRAWS water out of the skimmer FASTER than an open pipe! So fast in fact that I could now use the gate valve to actually control the water level! When the gate was just open, the pump dumped in more water than the outlet could handle, with the submerged (and air hole less) outlet pipe, I sucked water out of the skimmer so that the gate valve actually did something!
I think that submerging the pipe may be irrelevant, if you just bend down a 90 elbow that goes to a pipe that is lower than the level you want the skimmer's internal water level set to, you will create a siphon (we all understand siphons at this point!). The 1"-2" bushing and the 2 inch coupler (which I drilled some under-the-waterline holes in) makes the outlet silent!
I will post a picture tonight when I get home, but if you even give a crap anymore, maybe you could try running a pipe with a 90 degree bend going downwards to create a siphon just to see if this theory is correct...if it is, then you can sell the EV-120 on eBay and NOT have to say that it is underperforming!
OK, I know I put too much "I did this, then I did that" but I felt the need to explain how I came upon this conclusion, so that you guys can trouble shoot your skimmers too.
This morning I had some nice foam rising into the collection cup...!
Hope this helps...someone!
V
