Grundfos Circulators - What's the difference?

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Marshy

Minister of Fire
Dec 29, 2016
840
NY
I need to replace a Grundfos UP 15-42F that is not working in one of my zones. It is blue in color but I also have a red one for a different zone. I dont understand the difference between the two. Can anyone explain a difference besides color?
[Hearth.com] Grundfos Circulators - What's the difference?

[Hearth.com] Grundfos Circulators - What's the difference?
 
Do they have different electrical hookups? Looks like one has a pig tail of some kind with it - the other just bare terminals? I wouldn't think the circ itself would be any different.
 
Might be an older model..? I wish I could find some manuals or something on them.
 
Pretty sure they also take their circ bodies and adapt or mod them for specific applications. My LK810 has a 15-58 in it but I dont think I could unbolt it and put an off the shelf 15-58 in. Although I haven't fully investigated that. ;hm
 
Agree on the logo but it may have come off a blue boiler like a Boderus.
 
Well, here is the blue in I have.
[Hearth.com] Grundfos Circulators - What's the difference?


Here is the red one I have.
[Hearth.com] Grundfos Circulators - What's the difference?


The one not working is the blue one. Best I can tell either one will work, both are UP15-42F... I'd rather not have to buy an entirely new pump if I didnt have to but I dont know that i can get just a new motor and impeller.
 
Yeah, that's what I was starting to conclude. A whole new pump appears to be the same cost as the kit.
 
I've seen black (instead of taco green) Taco circulators that came with the boiler when new. No difference other than paint from what I could see.
 
The red one has the 230 max temp stamp and the blue one doesn't. Maybe the blue is for cold water?
 
The first blue one has the same max temp
 
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The red one has the 230 max temp stamp and the blue one doesn't. Maybe the blue is for cold water?

Woops, it was written differently and I missed it. Sorry.
 
I wonder if red is indoor use only but blue is indoor/outdoor..?

Idk, if I get a chance I'll ask supply house.
 
Hi sir.



Hope everything goes well with you.

Now I'm facing similar issue in my home. My old blue pump is not working properly and now I am hesitating to buy the new red one coz I don't know whether it will be compatible.


Thank you brother and looking forward to your response.



Ben
 
The only difference I see is one is ULc the other is UL and CSA. I'm willing to say they are identical as UP 15-42 F is what identifies the pump.
 
The red one says for indoor use only, no such writing on the blue one