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RB-24E, GuardDog Electronic, 24V Low Water Cut-Off - (Water)
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144692 has been discontinued
Discontinued July 8, 2025
This product was discontinued by the manufacturer.
MANUALS (4)
This item replaces: 144685, RB-24, RB-24E
Suggested Alternative:
RB-24SE, GuardDog Electronic, 24V Low Water Cut-Off (Water)
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Product Highlights
–
160 MAX PSI
250°F Max Temp
24V
5-3/4"
Threaded Connection
Description
–
Features & Benefits:
- Specifically designed to shut off the Burner if there is a unsafe water loss
- For residential applications
- Compact size
- Easy to install and wire
- Automatic reset feature resumes operation after a power outage when water is on probe
- Green power on indicating LED
- Red low water indicating LED
- Solid state operation
- 3 ft. harness cable included
- Brass threads provide a metal-to-metal seal that ensures a leak-free installation
- Integrated wrench flats enable secure installation without damage to the housing.
- McDonnell & Miller's patented self-cleaning probe minimizes scale build-up and extends the recommended cleaning interval to 5 years.
- "Plug & Play" wiring harnesses are available for most residential gas-burning boilers.
Specs
–
| Application: | Hot Water Boilers |
|---|---|
| Type: | Electronic |
| Reset Type: | Automatic |
| Max Pressure (PSI): | 160 |
| Max Temp (F): | 250°F |
| Sensitivity: | 15000 ohms |
| Voltage: | 24V |
| Length: | 5-3/4" |
| Width: | 1-7/8" |
| Max Ambient Temp (°F): | 120°F |
| Connection Type: | Threaded |
| Thread Size: | 3/4" |
| VA Rating: | 2.5 |
Questions?
Speak with a real person who will go out of the way to help!
Call or text 888-757-4774
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Friday
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Saturday – Sunday
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Compare Similar Products
Brand
Application
Reset Type
Voltage
CURRENT ITEM
Hot Water Boilers
Automatic
24V
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Product Reviews
4.94 out of 17 reviews
94% would recommend this product
5 star
94%
4 star
6%
3 star
0%
2 star
0%
1 star
0%
Showing 1-10 of 17 reviews
Definitely recomend SH.con
Good value quality parts fast shipping
Chris
Buffalo ny
2 years ago
Verified Buyer
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What a great company to deal with
Quick shipping and help on the phone.Supply House has great prices and tremendous service.
Jimmy D
Nj
3 years ago
Verified Buyer
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right part and on time
Got exactly what I needed, problem solved. Thanks
DW
Western MA
3 years ago
Verified Buyer
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i would by it again
Small enough to fit anywhere in the system, and easy to install
Tony
New Jersey
3 years ago
Verified Buyer
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Another GREAT PRICED SupplyHouse product
Worked and fit perfectly!! Fast shipping!!
Rich
NY
3 years ago
Verified Buyer
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Excellent Service
I was really surprise to find the product delivered to my doorstep the next day! Installation was really easy and it worked properly from day one.
Joe
Phoenixville, PA
4 years ago
Verified Buyer
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Prompt delivery !
Excellent service
Bharat Shah
Iselin, NJ
4 years ago
Verified Buyer
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Great service and delivery time.
My purchase was shipped the day that I ordered it and it arrived in 2 days.
Dan
Western, NY
5 years ago
Verified Buyer
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YES!!!!!!!!
This was a replacement for mine that went bad. VERY fast shipping, and installed in 30 min! Thank you all for your assistance. You are wonderful. If I need any parts, I know where to go! TY!!!!!!!!!!!!!!!!!!!!!!!
Pete
NJ
5 years ago
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RB-24E, GuardDog Electronic, 24V Low Water Cut-Off - (Water)
This LWCO is used on a Heat Transfer Products Munchkin boiler. The previous LWCO was about 15 years old and the red indicator turned on intermittently and also developed an intermittent buzzing sound. When I removed the old device the piece that keeps the water sensor clean was about to fall off. Problem avoided.
Stefano
New Providence, NJ
6 years ago
Verified Buyer
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Product Q&A
2 Questions2 Questions
Q: Will the M&M model RB24-E lwco operate correctly with a 50% mix of propolyne glycol in a residential gas fired hot water boiler?
Asked by Fred 8 years ago
Add your answer
Verified Reply- Water/glycol mixtures up to 50% concentration may be used.
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Q: How can I get the wiring diagram? Can I use the same wiring harness
Asked by 15 years ago
Add your answer
Verified Reply- PexSupply StaffPlease refer to the Installation Guide for this LWCO below: http://s3.pexsupply.com/manuals/1320960093621/67941_PROD_FILE.pdf
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