Comline 9012 DC skimmer not performing as should

[Idech]

Hello @rvitko,

I’ve had my internal skimmer for about 2 years and a few days ago I noticed big bubbles of water accumulating on the external side of the bottom plate. It looked like the plastic might have been cracked, leading to bubbles forming.

So I took it out of the tank to check and there were no cracks. I figured I’d do maintenance on it and test it again after (last maintenance was done 10 weeks ago). So I cleaned the casing inside and especially the impeller and the pump. The impeller looked okay. What looks like a screw on top was worn a bit, (I didn’t take a picture) but nothing major so I just reassembled it and put it back in the tank.

It’s been over 24 hours now and it’s not skimming as it should. Even if I adjust the amount of air on the controller, bubbles aren’t rising as they always did in the cup. Before I would turn the knob almost completely down (about 22%) because it would overflow otherwise, and it did a good job like that.

Now I’ve adjusted the knob 1 1/2 notch up but there aren’t more bubbles rising in the cup and skimmate isn’t collecting faster. It doesn’t seem to be skimming much (it looks like the same level as yesterday), and it’s skimming wet.

Do you think this would typically be a problem with the impeller itself, or the electronic controller and pump (which looks like it needs to buy as a set together) ?

Thank you.

 

[rvitko]

Not likely to be the pump or controller. Is the air intake clean? The nipple the hose attaches to on the impeller cover. This clogs with salt and has a big impact on performance. There is no screw on the needlewheel, a photo would be a big help, a broken or worn impeller is a likely cause. The other issue can be having the impeller cover on wrong, it can install 2 ways but when on the right way it is symmetrical and the solid side is against the pump mounting plate. Another common cause is having the cup installed wrong, the front has 3 tabs, these tabs tuck in behind the front of the skimmer and if they sit on the front of the skimmer, the gap lets air/foam escape and the cup won't collect anything.

 

[Idech]

Not likely to be the pump or controller. Is the air intake clean? The nipple the hose attaches to on the impeller cover. This clogs with salt and has a big impact on performance. There is no screw on the needlewheel, a photo would be a big help, a broken or worn impeller is a likely cause. The other issue can be having the impeller cover on wrong, it can install 2 ways but when on the right way it is symmetrical and the solid side is against the pump mounting plate. Another common cause is having the cup installed wrong, the front has 3 tabs, these tabs tuck in behind the front of the skimmer and if they sit on the front of the skimmer, the gap lets air/foam escape and the cup won't collect anything.

I checked the air intake and it looked okay but I will double check. How would you clean it ? Is running warm water in it okay (after removing the cap) ?

After letting it rest for the night, I cleaned the cup this morning and did some more tests. I turned the knob all the way up and it immediately responded with normal over skimming. It seems to be working now.

I’ll keep checking it this week and will come back to this thread and implement your tips if it happens again. I’ll post photos next time.

Thanks and have a great day !

 

[rvitko]

It depends on the degree of salt build up, warm water and vinegar may be enough if it is fairly clean, but they can get so obstructed you need to ream them out and for that I prefer a small drill bit pushed and twisted by hand to get through and get most of it, then follow with soaking. You can use fairly hot water really, as hot as you might get from a faucet.