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$201.44 each
In Stock
Get 3 Tue, Jul 7
Order by today, receive Tuesday
MANUALS (2)
Free Shipping This item ships free
Easy Returns No restocking fee for 90 days
Product Highlights
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UPS15-42F, UP15-42B5/B7, UP15-42BUC5/BUC7, UP15-42SU/SF
Description
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Grundfos 506173 Cartridge Kit for Select UP Series Circulators
A genuine Grundfos replacement cartridge kit used to restore operation in select Grundfos UP/UPS series circulator pumps without replacing the entire pump body when the correct cartridge kit is required.
Key Features
Compatibility & Applications
Installation & Operation Notes
Maintenance & Troubleshooting
User Reviews & Q&A Summary
A genuine Grundfos replacement cartridge kit used to restore operation in select Grundfos UP/UPS series circulator pumps without replacing the entire pump body when the correct cartridge kit is required.
Key Features
- Replacement cartridge kit (service "wet end"/rotor-style replacement) for select UP/UPS circulators
- Listed for use with UPS15-42F (115V), UP15-42B5/B7 (115V), UP15-42BUC5/BUC7 (115V), and UP15-42SU/SF (115V)
- Application listed: Heating
- Type listed: Replacement Part
Compatibility & Applications
- Listed for these specific pump models: UPS15-42F, UP15-42B5/B7, UP15-42BUC5/BUC7, UP15-42SU/SF (all 115V as listed).
- Must only be used where the manufacturer specifies this exact part number: 506173.
Installation & Operation Notes
- Installation should be performed by a qualified hydronic/HVAC service technician.
- Reference the pump and system service/installation documentation for safe isolation, correct disassembly/reassembly, and proper checkout after replacement.
- Grundfos UP-series guidance includes important installation/operation cautions (for example, do not operate the pump without water circulation, and avoid mounting positions that place the pump shaft vertical).
Maintenance & Troubleshooting
- This kit is typically used when troubleshooting points to a failed cartridge/rotor assembly (for example, a seized or non-operational circulator) and the pump body is still serviceable.
- If the pump still fails after installing a new cartridge, user feedback highlights checking the pump housing/body condition (some report discovering the pump housing was worn) before assuming the new cartridge is the issue.
User Reviews & Q&A Summary
- Restores circulation / avoids full pump replacement: Many reviewers report it brought a boiler/radiant circulator back online and saved the cost/effort of replacing the whole pump.
- Ease of install: Common feedback describes a quick swap (often around 15 minutes) with no wiring changes - typically removing a small set of screws/bolts to exchange the cartridge.
- Removal can be the hard part: Several users note the old cartridge can be difficult to remove if it's swollen or seized, requiring persistence.
- Obsolete-pump support & spares: Some reviewers buy it specifically because their pump model is discontinued and/or to keep a spare on hand.
- Fit/diagnosis caution: At least one review notes the cartridge was correct, but the pump housing/body was worn and needed attention instead.
Specs
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| Application: | Heating |
|---|---|
| Type: | Replacement Part |
| Used With: | UPS15-42F UP15-42B5/B7 UP15-42BUC5/BUC7 UP15-42SU/SF |
Contact
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Happy Independence Day!
Our Customer Support will be closed today in honor of Independence Day. We will be back tomorrow to answer your questions.
Call or text 888-757-4774
Special Hours
Closed Now
Monday – Thursday
8am–7:45pm
Friday
9am–7:45pm
Saturday – Sunday
9am–5:45pm
Product Reviews
5 out of 14 reviews
100% would recommend this product
5 star
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Showing 1-10 of 14 reviews
yes
I received correct one. My pump housing was worn out. Had to return for credit
d
Texas
7 months ago
Verified Buyer
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Perfect fit and performance.
Both products are exactly what were specified.
Mike
Campbellsport Wisconsin
12 months ago
Verified Buyer
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Great service great part
The staff was great finding me a replacement part as the assembly was no longer available. It fit perfectly and saved me almost $300. Thanks
Cshin
Michigan
4 years ago
Verified Buyer
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Radiant heat pumpa
This was just what I needed. A hard to find part, but you guys had it. It repaired the system. Thanks
Mike
Issaquah, WA
4 years ago
Verified Buyer
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If you have a failed pump, buy this
I bought a replacement rotor/motor assembly for my Grundfos pump. If was easy to replace, took 15 minutes. Now my boiler circulation pump is back up and running.
Ryan
Burien, WA
6 years ago
Verified Buyer
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A Quick Replacement Option
Installed simply, however, with some difficulty of removing old cartridge. No body of the current pump needed to be replaced.
ZSupplyH
Accord, NY
6 years ago
Verified Buyer
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I will buy again
Cartridge is simple to install
Terry
Winchester ca
6 years ago
Verified Buyer
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Great Repair part
When this Grundfos pump is installed at times it overheats causing the pump to freeze up. The availability of this sel-contained pump rotor allows repair without removal of the pump body. This is accomplished by shutting off the water supply, then removing the 4 hex screws attaching it to the main pump body. You now have access to the armature. Pull the rotor body and replace (sometimes it can be swollen and a bit difficult to remove, but persevere).
Replace the unit and you're good to go....no wire changes, just the 4 hex screws....simple!
Henry
Virginia
7 years ago
Verified Buyer
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Great rebuild kit for a now obsolete pump
This is my second one of these -- not because the first one went bad, but because I wanted a spare "just in case". Easy to install and no plumbing changes. Original pump siezed up after about 6 years. The first replacement has been working fine for about 4 years now. I may not ever need a second rebuild kit, but if I ever do I have one.
DSO
Los Gatos, CA
7 years ago
Verified Buyer
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Designed to be replaced
The cartridge in my discontinued gGrundfos 15-42su had a broken ceramic shaft. I realized while trouble shooting that this part was designed to be replaceable while the flow assembly is still attached to the system its a Great design and a super easy fix without tossing the whole assembly!
While the kit seems spendy, its less than a new pump and supply house had the lowest price. Unfortunately supply house shipping to Washington state took 9 days which was more days than I expected.
Happy homeowner
WA
10 years ago
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Free Shipping
On orders over $99
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Shipping PolicyEasy Returns
Returning items is as simple as 1-2-3
Ordered the wrong product? Item damaged in transit? Our 3-step process makes returning products easy – even up to a year after purchase – with no restocking fees on returns made within 90 days.
Return Policy