9410 DC tuning and water depth?

[dpstrand]

I just purchased a 9410 DC skimmer and have had trouble getting it dialed in. It has significantly overflowed the skimmer cup 3 times now since installing it yesterday afternoon. It is sitting in about 7.5" water height, and I have tried roughly 30%, 50%, 70% on the air dial on the controller with the same results.

I think I should raise it up by an inch or so, but given the current depth where should my air percentage be set to roughly? Is there anything else I can do to prevent it overflowing?

One other question, the pump seems pretty quiet however the bubbles popping in the neck is fairly loud, much more noticeable than the vertex omega 130 that it replaced. Is there anything I can do to quiet this air/bubble popping sound?

 

[rvitko]

Try 6" of water and the pump speed at around 20-40%, for reference the DC pump at 50% is about the same strength as the AC pump and you would have to close the air on the AC model about 30%. You can run a higher water level but that 1.5" difference is more work for the pump to fill the skimmer so you can accomplish more aeration/gas exchange by running the pump on higher speed. The pump will generally be run on the lower end of the speed. It is also not unusual to have the cup fill quickly on a new install but that will improve over the first week. If the bubbles are coming through the vents in the cup and that is making the noise, you can dip a q tip in vegetable oil and smear a thin film there and it will pop them when they touch it so they don't escape.

 

[dpstrand]

I raised it up by just over an inch and it has not overflowed again yet.

However the noise is still an issue. I took a video and an image, linked below. It seems there are two sources of noise:

1. Air. It is not the bubbles coming through the lid. I assume it is air making the noise but I really don't know for sure. It reminds me of a bag of instant pop popcorn in the microwave, i.e. a low frequency fast popping noise. You can hear it constantly in the video: https://youtu.be/ycZKGg8lRjk

2. Pump. While experimenting with it last night I found that if I pinch the air line, the pump makes a loud noise. Also at higher power the pump becomes much noisier. Both demonstrated in the video above. I took the pump out and pressed the bushings in tight, and the rubber part of the front bushing still seems slightly lifted. I can't see the rear bushing enough to tell. Picture of the front bushing from the side: https://photos.app.goo.gl/KA2Tvd2BR7CkpcTA7

 

[rvitko]

1) The silencer is upside down, short hose attaches to the pump.

2) The grinding with the air closed off is normal, the vacuum created pulls the impeller into the impeller housing.

3) The noise from speed increase is not normal, the red part of the bushing should be even so only the lip is above the plastic, I would try to seat both with a firm push. If the noise persists, let me know and we send a new impeller set.

4) I assume the cup retainers were not modified? The cup fits very tight in 4 protrusions to prevent the cup from rattling, I have seen people cut these off and they are a deliberately engineered part. If these were not removed or cut down, I would assume the noise is one of the following:

1) The lid is rattling, this usually has a higher pitch in my experience, but it is a possibility. Make sure the lid is secured.

2) The skimmer is rattling on the base, make sure the rubber feet were installed.

3) The silencer has water in it, this tends to result in a coffee maker like noise (percolating) it is similar but not quite what I heard. The silencer will tend to get water in it if the skimmer is foaming over and short of removing it and draining it, it takes a few days to clear on its own.

 

[dpstrand]

Thank you Roger! I will reverse the silencer, and try to press the bushing in again, and re-test. I have not modified the collection cup in any way. I would describe the constant sound as a coffee percolating sound, spot on description in my opinion. Perhaps it is due to the silencer being backwards, but I will also check it for water as the skimmer did overflow a few times on day 1.

 

[dpstrand]

I reversed the silencer and drained some water that was accumulated inside. I am happy to report the percolating sound is gone!! It is so much quieter now. I did not re-press the bushings yet, once I do this I will report back on the higher power pump noise. Thank you Roger!

 

[rvitko]

Great news!