9005 collection issue

[vbsaltydog]

I have a Tunze 9005 skimmer that seems like it is having an issue with collecting the skimmate properly. The skimmer works but instead of having the bubbles flow over from the reaction chamber into the cup and then turn to liquid in the cup it just builds up bubbles in the collection cup and then every now and again will make a gargling sound as the pressure from the reaction chamber cant escape due to the bubbles consuming the collection cup and so the bubbles will come up through the small holes where the collection cup top is aligned or sometimes the entire collection cup will rise up off of the reaction chamber to release the pressure from the chamber.

Any ideas?

 

[vbsaltydog]

After doing some reading I decided to run the skimmer in a vinegar bath of about 4 cups of white vinegar to 5 gallons of ro/di water in a 5 gallon bucket with the skimmer in so after displacement is is probably 4 gallons of ro/di to 4 cups of vinegar or 1 cup vinegar per gallon of ro/di

The skimmer is running with the adjustment screw removed and immediately, the skimate is much heavier/denser with a smaller bubble consistency. I noticed that there is a hole in the back of the housing at the top reaction chamber level. I don't know what the hole is for but I assume it should be submerged during operation? Perhaps it was not submerged while the skimmer was in my tank and this caused the "fluffy" skimate?

Any info is appreciated.

 

[rvitko]

I don't really have an answer for what you describe. I have never seen that before. An old trick we used to recommend in the manuals years ago may help. In a new tank or recently overhauled tank the foam can be very fine and light and escape through the vent holes in the cup. We recommended carefully smearing the outer lip of the cap on the skimmer cup with vegetable oil, this popped the bubbles and prevented foam from blowing out of the vents. This problem tends to solve itself given time.

The hole in the back vents out water at a specific height. In these skimmers a column of water is what seals the cup. It forces the lighter air water mix up the cup and eliminates gaskets and fittings to seal the cup.

 

[vbsaltydog]

Thanks Roger.

 

[vbsaltydog]

OK. It is working better after the vinegar bath but the air adjustment screw is wide open too so it could be the vinegar, the screw, or both.
I think the screw was too tight before but I had/have a reason. When the air screw is open enough to increase the skimate production I get a sound that resembles "engine knock" and it is loud enough to be disturbing. Any ideas what is causing the knocking sound and how to fix it other than to tighten the screw until it is quiet as this also henders skimming.

Thanks for all of your help.

 

[clownnrnd]

I would take it apart and check to make sure all the air line connections are secure and that the pump is seated correctly in the comline housing as shown on page 8 of the owners manual.

I run the 9005 and open up the blue screw about 4 turns. I don't know what the knocking sound would be. I would look at the impeller that is the only thing that moves that could possibly knock. The only other thing is sometimes if you suck up water into the air intake the silencer will make a gurgling sound. Maybe if one of the airlines has come unattached it could be making a gurgling noise???

Chad

 

[vbsaltydog]

Thanks for the reply. As far as I can tell, there is only 1 hose (from the silencer to the venturi) and it is attached on both ends or else you do not get any bubbles. The pump will only go into the housing one way and allow the bottom of the housing to fit into place so I dont see how that could be the problem. The knocking sound only happens when the screw is out a good amount. If the screw is closed enough to where it is finger tight then there is no knocking so I am not sure what is going on there but something is definitely wrong.

Any info is appreciated.

 

[rvitko]

I wonder if it is submerged too deep? The marked water line should be considered an absolute maximum. US 60Hz pumps are slightly stronger than the 50Hz versions and it may be necessary to raise the skimmer about a 1/4". My guess is the knocking sound is caused by water entering the airline. When you open the airscrew the increased suction draws in water.

 

[vbsaltydog]

Thanks Roger.

I took the whole thing apart yesterday and checked all of the internals to make sure that everything was seated correctly and that nothing is loose and everything checked out so the only thing it could be is water being drawn in like you said or some thing inside the venturi.

I cant see inside the venturi obviously and from what I have read, its simply a bottleneck that forces the air flow to compress so there probably isn't anything in to break or come loose.

I will raise the unit as you suggested and report the results but where would the water be drawn in from? The only way water can get into the air flow system is through the screw hole or the plastic tube from the air screw that is part of the housing and this is sealed so it isn't a logical point of entry.

Could it be that there is a crack in the integrated air tube that is pulling water in when enough suction is applied?

 

[rvitko]

The hole the screw goes in to is part of a T. The screw covers the down leg of the T and as you back it out it opens the hole for more air flow. The air is sucked in through a hole that is at the back of the screw under the cup. If the water level is high under the cup it will suck in water at this point.

 

[vbsaltydog]

Understood. I will check the water level and report my findings.

Thank you for the prompt response.

 

[vbsaltydog]

Roger,

If you remove the collection cup and cover the inside and outside holes in the screw T with your fingers then the bubbles stop in the reaction chamber and the clicking stops as well. If you uncover EITHER the front or the back of the screw T then the clicking starts, as does bubble production. This negates the idea that the clicking is being caused by water intake through the air line (at least at the T level).

Any other ideas?

 

[rvitko]

I have no other ideas, I would try raising it and if that doesn't solve it I would send it in to us for repair.

 

[vbsaltydog]

Thanks Roger. Where can I find info on where to send it to and the cost of repairs?

 

[rvitko]

I don't know that there will be any cost, it has a 2year warranty.

Tunze USA
305 Victor St
Austin, TX 78753

 

[vbsaltydog]

Thank you.

 

[vbsaltydog]

Roger,

If I decide to send it in for repair, what do I need to include in the shipment?

I have the original receipt from the pet store where it was purchased on 02/28/07 so it sounds like it is still under the manufacturer's warranty.

Is a UPS shipment with:

(1) the skimmer.
(2) a copy of the receipt.
(3) a note regarding the symptoms to troubleshoot.

sufficient?

What is the average turn around time on the repair?
How does Tunze ship the unit back to me?

Thank you for your continued support.

 

[rvitko]

Just be sure to pack it carefully, keep in mind the cup can be easily broken.

Typical turnaround on a repair like this is 72hrs. That is the amount of time it would be here being repaired and reviewed. Most repairs are 24hrs but something like this we would need to set it up and run it.
We ship back by UPS ground.

 

[vbsaltydog]

Thanks Roger. I will send it out tomorrow.

 

[smatter]

The knocking sound is large bubbles popping inside the reaction chamber. Mine does this for a while after a thorough cleaning when the air screw is wide open. It isn't a problem and subsides with time.