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$183.74 each
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Product Highlights
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115V
Description
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Grundfos 506172 Cartridge Kit for UP15-18SF, UP15-18SU
A replacement pump cartridge kit used to rebuild select Grundfos UP15-18 circulator pumps (UP15-18SF/UP15-18SU) without replacing the entire pump body.
Key Features:
Compatibility & Applications:
Installation & Operation Notes:
Maintenance & Troubleshooting:
User Reviews & Q&A Summary:
A replacement pump cartridge kit used to rebuild select Grundfos UP15-18 circulator pumps (UP15-18SF/UP15-18SU) without replacing the entire pump body.
Key Features:
- Replacement part (cartridge kit) for select Grundfos UP15-18 circulators
- 115V
Compatibility & Applications:
- Listed for: UP15-18SF and UP15-18SU
- Q&A fit note: Not listed as compatible with UP15-18BUC7 (a different cartridge kit is identified for that pump)
- Must only be used where the manufacturer specifies this exact part number: 506172
Installation & Operation Notes:
- Installation should be performed by a qualified hydronic/heating technician or plumber
- Follow the circulator's service/installation documentation and applicable codes/accepted practices
- Manufacturer operating/safety guidance for UP(S) 15 circulators includes:
- Installation/operation must comply with national, state, and local regulations and accepted codes of good practice
- Before starting, the system must be filled with liquid and vented
- Q&A content confirms the kit includes an O-ring
- Review-reported install notes commonly mention a quick cartridge swap; one reviewer notes needing a press to install the cartridge evenly without contacting the impeller (tooling/technique dependent)
Maintenance & Troubleshooting:
- This kit is typically used when the circulator becomes noisy, wears out internally, or stops performing normally, and you want to rebuild the pump without cutting piping
- Grundfos UP(S) 15 troubleshooting guidance includes: if the pump doesn't run, the shaft can be rotated manually (with power off and isolating valves closed) via the access screw in the nameplate area, then restoring pressure before restarting
- If issues persist after replacement, use the pump/unit troubleshooting steps to confirm the problem isn't related to air in the system, improper fill/venting, or other system conditions
User Reviews & Q&A Summary:
- Reviews are strongly positive overall and frequently describe:
- A significant cost/time saver versus replacing the entire circulator (especially when the housing is still good)
- Straightforward replacement and quieter operation afterward ("basically silent pump" / "worked like a charm" themes)
- Mixed feedback includes:
- Price sensitivity (some feel it's expensive versus replacing the pump with a lower-cost alternative)
- Tooling/skill considerations (one reviewer felt a press was needed for proper installation)
- Q&A highlights:
- Not compatible with UP15-18BUC7 (different cartridge kit identified)
- O-ring included
Specs
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| Type: | Replacement Part |
|---|---|
| Voltage: | 115V |
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Product Reviews
4.71 out of 21 reviews
95% would recommend this product
5 star
71%
4 star
29%
3 star
0%
2 star
0%
1 star
0%
Customer Images
Showing 1-10 of 21 reviews
this is an easy fix for a grundfo circu pump
my old one still works, but with a loud noise. not pleasant. so i was looking for a replacement. although there are some new circu pumps available under $100, my old unit is soldered in line. which leaves me with swapping the old cylinder as the only easy option. there are two items available on this website, one for $230+, the other $173+, this one works perfectly for my up15-18b5.
dale
boise, id
5 months ago
Verified Buyer
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Pricey, but much better than replacing the entire pump.
10 minute job - knock out the old one and slide the new one in. Clever design and we're back to a basically silent pump. Considering the original lasted 22+ years, I'll gladly pay the price for the guts.
Karl
Maryland
9 months ago
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I'm sure these are good quality, but in my opinion overprice
Great design, and simple installation if you have the required tools. I found it necessary to use a hydraulic press to be able to evenly install this cartridge without contacting the impeller. Not sure the average Joe would be able to properly install this cartridge. With so many cheaper Chinese circulating pumps available, not sure this cartridge was a good investment.
Ken
Queen Creek, Az
1 years ago
Verified Buyer
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5 Star
Right product and on time
Dusty
Missouri
2 years ago
Verified Buyer
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Worked well
Easy to order, delivered on time and priced ok.
Jim
Morro Bay, CA
3 years ago
Verified Buyer
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Worked like a charm
Easy peasy to change out the cartridge. Remove 4 Allen screws one large flat head screw, push out the old cartridge, slip in the new one and put the screws back in and you're done.
DJ
Tucson Arizona
3 years ago
Verified Buyer
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Product worked
Worked as advertised and expected. Saved me from buying a new unit
bounce
Austin, tx
4 years ago
Verified Buyer
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Cost saver
Fit and worked great. Also cheaper then replacing complete circulator which was discontinued
Happy plumber
Mooers NY
4 years ago
Verified Buyer
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i would buy this product again
Perfect fit and easy rebuild
N/A
Cottonwood, AZ
4 years ago
Verified Buyer
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Saves time and money
A great design just replace the worn out motor and keep reuse the housing, no need to change the plumbing.
Joe
Surprise AZ
5 years ago
Verified Buyer
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Product Q&A
2 Questions2 Questions
Q: Is this product compatible with Type: UP15-18BUC7
Asked by Carlos 10 years ago
Add your answer
Verified Reply- SupplyHouse StaffNo, it seems that sku 506174 is the correct replacement cartridge for the UP15-18BUC7 pump.
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Q: does it include o-ring?
Asked by Forrest 11 years ago
Add your answer
Verified Reply- Supplyhouse StaffYes, it does.
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