Deadheaded Taco 007 Noises Solution

D107

@Mark Eatherton here's an old thread and comment of yours on the topic:

Although it's not considered a good idea...and I wouldn't recommend that any pump be dead headed for any extended period of time, I have come across a Taco 007 that had been dead headed for 2-1/2 winters, and it was just fine. It's the BIG pumps that you have to worry about. When dead headed, you are pouring a SIGNIFICANT amount of energy into a small amount of water and super heating it. When the pressure is dropped, the water is no longer water, but becomes steam and occupies 1700 times more space than it used to when it was water.

I once saw the power head from a Grundfos circulator that had been blown through two sheet rock walls and embedded in a cinder block wall. It can happen, but it takes time and when talking about small circulators is not as critical. Better safe than sorry just the same. ME

We are selling the family house with our Buderus G115, two zone, DHW with three TACO 007s. About 6 years ago in the shoulder season, probably after removing air from the system after installing new shutoff valves in the two basement radiators, the contractor left one of the system ball valves off for a few weeks. (Isolation valves were not closed.) Since that time I have not detected any problems except that that 007--unlike the others which run silently--often has a hum-gurgle small motor kind of sound, not loud but noticeable nonetheless. I'd like to leave the system in top shape for the new buyers, so my questions are these:
1-Is the noise normal?
2-One contractor has suggested that replacing the cartridge might be enough.
3-Is the cartridge the only thing likely to be damaged by this dead-heading? Impeller? Replace the whole unit?

hot_rod

Gurgle is usually an air issue not defective pump? Try a good purge before you change anything. Air in a circulator can make all sorts of strange sounds.

Do it with care or get a pro to help and loosen the flange bolts at the discharge and trapped air usually expels itself.

Air comes out of solution best than the water is hot, so purge and deal with bubbles them, but be careful with anything over 130F, it can produce 2nd degree burns quickly.

A squeal in more of an indication of a fried bearing surface or shaft.