I have got 3 models of Rena xp canister filter series. Xp1 Xp2 and Xp4. Xp1 and Xp2 are very silent , but my Xp4 is making some noise.
I dont know if just the size of the model, but im pretty sure its not air in the filter thats the problem. Im guessing its coming from the impeller unit. And each time i turn the filter on the impeller makes a loud noise for a few seconds. Then it goes back to its normal vibrating sound, thats louder that i would like it to be. Any ideas what might be wrong ?

Yes it seem to push te amount  water would expect. May be the Xp4 makes more noise ?

well after trying alot of things, one finally worked. I readjusted the tubings after moving the filter closer to the intake. Now i would say the noise has gone down somewhat. To a level i can live with

The Renas do this sometimes. While it doesn't seem to affect them it can lead to problems later on, like noise, leaks, them to stop running, etc.

When the filter is properly functioning, all air is expelled from the system in the first 30-60 minutes. If you still have air after 60 minutes then something is probably awry.
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