Repair of circulation pump PMM Siemens ⇐ Siemens

[Artyom Borisovich]

My Siemens PMM is 8-9 years old, it stopped turning on, when turned on it beeps for 1-2 minutes and then there is silence. I called the repairman, who announced the verdict that the circulation pump had died and needed to be replaced along with the heating element. The pump itself with tension is 8500 + labor 2000 rubles. I took a time out, paid for the diagnostics and after the technician left, I disassembled the circulation pump, on this site there is how to disassemble it (to repair the heating element), but you don’t need to remove the heating element.
Half the pump, then insert a flat blunt one under the pump impeller an object such as a kitchen spatula and resting on the outer mating surface (where the rubber band is inserted), the rubber band must first be removed, and we pull out the pump rotor with the pump wheel. We unscrew the pump wheel clockwise (there is a left-hand thread). On the bottom of the pump rotor shaft there is a sleeve - a sliding bearing and on top under the pump wheel there is another similar sleeve. The bushings in my pump were worn out, as can be seen in the photo (black graphite bushings are old, white and translucent new ones). If anyone needs it, I can send you a drawing of the bushings. I went to a turner and ordered 2 fluoroplastic bushings, 2 from caprolactane (for 1000 rubles)

, I first installed 2 fluoroplastic bushings in my pump, assembled everything and everything works great again!

[Cuth]

What brand of fluoroplastic did you order?

[igor]

In theory, it seems to me that the rotor shaft still needs polishing. And even better - a groove with polishing. The bushing bearing must also be compatible with the new diameter of the rotor shaft after grooving and polishing. The fact is that after work, a broken graphite bearing leaves scratches on the shaft (they can be seen and felt to the touch), and the shaft turns into a file. So a year or two or less, and your bushings will need to be changed again, as they will be cut off. But all this is purely my personal opinion.

[Guest]

Artyom Borisovich, can you draw a drawing of the bushings, or the internal diameter, or the gap between the bushing and the shaft

[Guest]

forgot to leave an email ( fam9@mail.ru )