Grundfos 15-58 Failure?

[BoiledOver]

Has anyone experienced a failure with one of these 3-speed circulators? Are all 3 speeds lost in any failure of the motor? Are there cartridges available or is the whole thing tossed? The storage loop circ is near the ceiling and I hard wired the speed selection to a location by the boiler controls. Wondering if it will be necessary to rewire a replacement or just swap a cartridge.

I have extras waiting on the shelf but was wondering about this today. Could possibly get by with just 2 or even one working speed till the end of a season.

 

[TCaldwell]

I have 7 of these, been running for 4 years. I have experienced no starts on the ones set on low speed after a summer of no use. Usually at the beginning of the season I'll run them on high for a few days, then turn them back to low. The start torque must just be low enough to be influenced by a dirty cartridge, not sure if their replaceable

 

[jebatty]

I haven't taken apart a 15-58, but I have a Taco and Wilo, and on these the motor with impeller unbolts from the impeller casing. No need to remove the plumbing side of the circulator. Just the motor impeller cartridge may be available, but they could be removed from a new 15-58 and installed on the old plumbing as best as Iknow.

 

[djbutt]

I let mine sit idle for a long time, when it didn't run I thought it was toast.

Turns out there is a plug you can remove. The motor shaft is slotted. Give it a spin with a screwdriver to free up the stuck impeller.

If it does not fix it, then it's junk.

 

[Bob Rohr]

Sometimes it's just a bad capacitor. Is the motor stuck? Remove the label and usually there is a screw you can remove and see the motor shaft, be careful hot water or steam may come out when the screw is removed.

If it is stuck it may be a water quality issue, or it runs dry being piped at a high point in the piping.

Many of the hydronic control relays have pump exercisers built in that runs the pump every day or so for 30 seconds to help keep them from seizing. Those wet rotor circs take a lot of abuse before they give up.

With the pump isolated from the piping just remove the allen bolts and replace the power head, a long T handle 5/ 32 or 4mm allen wrench works best. Replacement cartridges and motors are available, but usually cheaper and easier to buy another complete pump.

 

[BoiledOver]

Thank you all for your responses.

I failed to state that it was a hypothetical question as I have not had a failure.

My apologies to all.

 

[Eric Johnson]

Oh, I've got a bunch of hypothetical failures. Just take your pick.

I have one of those circulators and my only complaint is that the speed switch is a pretty cheesy design. Unlike the pump, which I understand is a pretty decent piece of equipment.

Bob's right about replacement parts probably not being worth the time and expense--other than the legitimate satisfaction of prolonging the life of an otherwise-good component. I don't know how long we can keep throwing away perfectly good items, but at some point it hopefully begins to cost more than it saves.

 

[varadhammo]

I have one of those circulators and my only complaint is that the speed switch is a pretty cheesy design. Unlike the pump, which I understand is a pretty decent piece of equipment.

Yes, I got one mail order with the speed selector shaft (little dinky white plastic thing) already broken, had to send it back. The electrical box cover wasn't screwed on and it shifted during shipping I guess, snapped that shaft right off. Good quick replacement though from supplyhouse.com, they sent it out immediately, 2-day.

The storage loop circ is near the ceiling and I hard wired the speed selection to a location by the boiler controls.

@BoiledOver, you mean you wired it to be able to select the speed remotely, or am I misunderstanding you? How does one do that?

 

[ewdudley]

you mean you wired it to be able to select the speed remotely, or am I misunderstanding you? How does one do that?

http://www.nofossil.org/index.php?choice=poormanvsc

 

[varadhammo]

http://www.nofossil.org/index.php?choice=poormanvsc

Cool, now do the same with an Alpha... ;-)

 

[BoiledOver]

Cool, now do the same with an Alpha... ;-)

LOL. Don't know about the Alpha.

To move to a remote location, disassembly of the circ switch box and circuit tracking via multi meter is required. Without going to the shop I will guess that 5 wires are required from the circ to the new switch(es). I used two 3-way house switches as they were here for the taking. Also at least one wire must be soldered, maybe 2. The truth is, if I had to do it again, I would have to figure it all out again.

 

[ewdudley]

Cool, now do the same with an Alpha... ;-)

http://www.wilo-canada.com/fileadmi...a_Sheets/26-Stratos_Interface_Module_0803.pdf