Broke impeller on my Tunze 6100

[Logzor]

It seems like the alarm on my Tunze 6100 goes off way more often than it should, perhaps it's my parameters but the pumps calcifies up very quickly. This time the alarm went off and it was really suck in there, I accidently broke off the tip of the impeller trying to get it out.

Right now I have it soaking in vinegar, hopefully I'll be able to get it out.

How much is a new impeller? Or, can I just replace the propeller and the plastics which connects it to the magnet?

Why is my pump calcifying so quickly? Is it becoming too hot?

 

[rvitko]

The mechanical cause would be a non thorough cleaning, where the hole in the magnetic rotor is clogged by calcium or the upper bearing (3000.610) is not removed and cleaned. These serve to pump cooling water through the pump, if clogged they jam up much faster.

If the pump was ever cleaned with a strong acid, anything besides vinegar or citric acid, the plastic may have swollen, reducing tolerances and resulting in more friction and heat.

If the calcium is above 420ppm, the pH is above 8.3 or the KH is above 12 or if magnesium is very high, all will aggrevate precipitation problems inside pumps and on heaters so the build up will happen very fast.

The drive unit is part 6100.700, the prop only is 6100.120.

 

[Logzor]

Roger, when I clean these pumps I remove the impeller, which comes apart into three pieces, the magnet/impeller, the bearing, and the rubber gasket that connects to the bearing.

I soak these three piece, the entire pump, and the grill in 5% vinegar for 24 hours.

Is there a step that I am missing?

I am still working on getting the old impeller out, which is slowly coming loose. It looks like a new one is around $30 which isn't too bad.

 

[rvitko]

That is it, just make sure the magnet spins smoothly on the bearing, it shouldn't actually be stuck to the bearing. Also check that the hole in the center of the magnet is clear and not jammed solid with calcium.

 

[Logzor]

I'm having trouble getting the magnet out of the motor. It is spinning freely but I think the bottom bear is cemented in. With all of the pieces I have broken off in the process of loosening it up, there isn't much to grab onto. I can get a pretty good grip with some needle nose pliers, though.

Any advice as how I can get it out?

 

[rvitko]

Carefully select a long deck screw and drive it into the center of the magnet, you can then grab the screw with pliers. Alternatively, go to any autoparts store and get a dent puller, it will have a small screw on the end, it is a mini slide hammer and is my tool of choice for this job, you can get one for $15 or so. Be very careful the screw is not to large, if you crack the magnet the job gets much, much harder.

 

[Logzor]

Thanks Roger, I'll try that when I get home. I think I have a few deck screws laying around.