9015 skimmer pump performance

[Mimbler1]

Roger, my 9015 hasn't seemed to be producing like it did, so I cleaned it, checked the venturi, switched in a new impeller drive while I clean the old one, and I didn't see any improvement. It works, but just doesn't have the vigor that it once did. Is there anything on the pump body itself that can produce reduced performance? If not, do you have any other ideas?

I realize that it could be some quality of the water (reduced organics, surface tension, etc.) but wanted to make sure I've explored all the hardware possibilites first,
thanks, Mike

 

[rvitko]

I would try running the whole skimmer submerged in a bucket of water with some vinegar added. Maybe some salt has accumulated in the inlet or venturi nozzle and this should clean the whole system.

 

[Mimbler1]

Thanks Roger - I think I figured it out today. I took the skimmer apart, and checked all air passages, and they were totally clear. I noticed however, that the air hose fitting into the venturi on my skimmer is a very tight fit into the venturi. I took some 1500 grit emery cloth and polished the fitting down enough to where I could insure that it is seated against the inner venturi when installed, and marked it with a knife score even with the outer edge of the outer venturi, so I could tell from now on when I assemble it that it is fully seated. I put it altogether, and it is now skimming like it used to. Apparently, the last few times I've cleaned it, I didn't get that fitting totally seated, and it was less efficient drawing air. The real tell-tale, is I now hear the air suction noise when running which I had forgotten about!

The funny thing is, that I had always known that the insertion depth of that air fitting is critical to venturi efficiency, and had wondered why Tunze relied on a friction fit to establish the insertion depth. Today was the first time I noticed that actually they had designed in a stop for it in the inner venturi at the ideal location! Reducing the od of the fitting just a smidge just makes it easier for me to reliably insert it till it hits the stop.

Oh, well, just another case of operator error, but now that I know what I'm doing, it won't happen again!

regards, Mike