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Ultra 155 - 123,000 BTU Output High Efficiency Boiler (Nat Gas or LP)
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383-500-703 has been discontinued
Discontinued June 18, 2013
This product was discontinued because the part number was changed by the manufacturer. No modifications were made to the replacement product.
MANUALS (8)
This item replaces: 383-500-403
Schematic Feature!
Replacement Parts
Direct Replacement:
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Product Highlights
–
123000 Max BTUs
Natural Gas, Propane
Direct Vent, AL29-4C, PVC
15 Year Limited (Heat Exchanger), 1 Year (Parts) Warranty
Hydronic (Water)
22-13/16" Width
Description
–
Heating equipment must be installed, commissioned, and serviced by a licensed and qualified professional in accordance with manufacturer instructions, applicable codes, and industry standards. Manufacturers do not accept warranty or technical support requests from homeowners or unlicensed individuals. All warranty and technical inquiries must be initiated by the licensed professional responsible for the installation.
**Series 3 Ultra Boiler
Key Features
- Gas fired water boiler with cast aluminum heat exchanger
- Venturi mixing body mixes air and gas providing higher efficiency
- Designed to operate in low temperature condensing applications
- Outdoor reset and domestic hot water priority standard
- Negative regulated gas valve precisely delivers gas to the boiler
- Electronic control module automatically adjusts blower speed and gas flow rate in response to environment
- Modulates with 5 to 1 turndown ratio
- Variable speed motor matches combustion output to heating needs
- High grade stainless steel burner features quiet operation, high efficiency, and cleaner combustion for low NOx applications.
Propane Conversion Orifice included for LP Gas Applications
Hydro-Core Near Boiler Installation Options::
**Series 3 Ultra Boiler
Key Features
- Gas fired water boiler with cast aluminum heat exchanger
- Venturi mixing body mixes air and gas providing higher efficiency
- Designed to operate in low temperature condensing applications
- Outdoor reset and domestic hot water priority standard
- Negative regulated gas valve precisely delivers gas to the boiler
- Electronic control module automatically adjusts blower speed and gas flow rate in response to environment
- Modulates with 5 to 1 turndown ratio
- Variable speed motor matches combustion output to heating needs
- High grade stainless steel burner features quiet operation, high efficiency, and cleaner combustion for low NOx applications.
Hydro-Core Near Boiler Installation Options::
- FT-2R45 1" Ultra Component Kit
Specs
–
| Width (Inches): | 22-13/16" |
|---|---|
| Fuel Type: | Natural Gas Propane |
| Vent Type: | Direct Vent AL29-4C PVC |
| Boiler Type: | High Efficiency |
| Color: | Slate Gray |
| Efficiency: | 95.6% |
| System Type: | Hydronic (Water) |
| Features: | EI/Spark Ignition Condensing Direct Vent |
| Vent Size: | 3" |
| Water Connection: | 1" |
| Gas Connection: | 1/2" |
| BTU Input: | 155000 |
| BTU Output: | 123000 |
| Warranty: | 15 Year Limited (Heat Exchanger), 1 Year (Parts) |
Questions?
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Call or text 888-757-4774
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Ultra 155 (S3)
Replacement Parts
SKU: 383-500-703
Brand: Weil-McLain
Search Parts:
SEARCH PARTS
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Product Reviews
4 out of 24 reviews
78% would recommend this product
5 star
67%
4 star
8%
3 star
4%
2 star
0%
1 star
21%
Customer Images
Most Liked Positive Review
Great UNIT A+
This is the second unit that I have bought and was even a replacement to an older unit. The install was easy since it was an easy bolt in rewire,(about1.5hrs.). Lots of nice better data than the old one and has been running GREAT!!! UNBELIVABLE QUICK SHIPPING!!!! I have recommend this site to many others and even brought it up to my normal HVAC service and he liked the price$$$$.
VS
Most Liked Negative Review
Horrible boiler
I don't understand all the positive reviews this boiler has tons of problems. First off the heat exchanger towards the bottom is almost impossible to clean if it plugs up. Secondly the cork gasket between the Venturi and gas manifolds leaks over time and or when unit is serviced it needs a new gasket most people don't carry this gasket. Ultimately what happens is gas comes out and I've seen a few of these boilers catch fire. It is a awful design and would never recommend one ever. And if I see one I recommend replacing it ASAP. Piece of garbage boiler do not buy or listen to the other reviews
Showing 1-10 of 24 reviews
Worst boiler ever
I have owned this boiler for 10 years and have never had a 6 month period without problems 1st heat sensor flame sensor is always getting dirty and shutting down constantly smells of gas not reliable at all. I would never purchase again.
Graig
Newton nj
2 years ago
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Low reliability
Constantly plagued with the red screen of death lock-outs, problems and low reliability. Very difficult to find technicians that are willing to service the unit and Weil-McLain has horrible support . Frequently needs parts that are very expensive. Not as efficient as claimed. Regret installing this boiler the day it was turned on. Have had to live many days in a frigid house and lots of cold showers. Not recommended at all.
Joe
New England
3 years ago
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Horrible boiler
I don't understand all the positive reviews this boiler has tons of problems. First off the heat exchanger towards the bottom is almost impossible to clean if it plugs up. Secondly the cork gasket between the Venturi and gas manifolds leaks over time and or when unit is serviced it needs a new gasket most people don't carry this gasket. Ultimately what happens is gas comes out and I've seen a few of these boilers catch fire. It is a awful design and would never recommend one ever. And if I see one I recommend replacing it ASAP. Piece of garbage boiler do not buy or listen to the other reviews
Boiler man
Washington
9 years ago
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Great UNIT A+
This is the second unit that I have bought and was even a replacement to an older unit. The install was easy since it was an easy bolt in rewire,(about1.5hrs.). Lots of nice better data than the old one and has been running GREAT!!! UNBELIVABLE QUICK SHIPPING!!!! I have recommend this site to many others and even brought it up to my normal HVAC service and he liked the price$$$$.
wro87
Central Il.
9 years ago
Verified Buyer
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I am impresses
I am very impressed with the quality and controls. Minor startup problem - after converting to Propane you also have to turn the throttle 2 full turns CCW - not mentioned in the manual. Information provided by the very helpful Weil McLain rep.
Father Bubba
NW Arkansas
10 years ago
Verified Buyer
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I install this boiler every chance I can
Super efficient and very reliable when installed to installation specs!
Grattans heating and cooling
Long Island New York
11 years ago
Verified Buyer
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Exactly what i expected
This product was delivered promptly and included every thing listed. Cant wait to use it!
Happy Paws
Central NY
11 years ago
Verified Buyer
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High-Efficiency, Low Reliability Boiler
Brand new unit installed in the Fall of 2014. 16 months later, the boiler has been down and in need of repairs 6 times. Circulator pumps (provided with the boiler by Weil McLain), circuit called (recalled in my unit before I purchased it - somehow "slipped through the process"), and generally unreliable performance from this expensive unit. Weil McLain's regional service rep and local distributor came out after the 4th failure was fixed and said "if it goes down again, we may have to do something". Still waiting for the "do something" part from Weil McLain.
Rob
Milton, VT
11 years ago
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Great Investment
Replaced a newer 85% efficency oil fired unit with this one. Oil cost us around $100.00 per month in the summer just to heat the domestic hot water. Now runs us around $20.00. Also makes very little noise, most of the time you do not even notice it is running. Very happy with this unit, and should pay for itself within the first four years of service.
Eric
Cowansville PA
12 years ago
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Great set up , easy install
I purchased the ultra 155 to replace the 1960 180000 btu weilmclain boiler that was original with the house. I would recommend the easy up manifold kit it makes the piping start up easy and takes out some of the guess work, the instructions are very detailed and tell you everything you need to know, from the piping layout to the gauge of wire for your pumps. The programming and startup is smooth just follow the instructions and use the four buttons to navigate through the screen. Yes I would purchase this again!!!
Cpt matt
Indiana
12 years ago
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Product Q&A
19 Questions19 Questions
Q: your easy-up manifold has the circulator pump on the return side of the boiler but the manual has it on the supply side. What is the difference?
Asked by 15 years ago
Add your answer
Verified Reply- PexSupply StaffHigh Efficiency boilers have large pressure drops, so it is generally recommended to put the circulator on the return side.
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- Sam
page 10 of manual states " install the boiler circulator only on the boiler return piping"
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Q: Can you change the orientation of the boiler circulation pump from vertical to horizontal? I have tight height requirement.
Asked by 15 years ago
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Verified Reply- PexSupply StaffYes, you can change the orientation of the pump.
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Q: Do you have installation manual for this boiler
Asked by Tom 15 years ago
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Verified Reply- PexSupply StaffPlease refer to the following manual: http://s3.pexsupply.com/manuals/1307982688254/56722_PROD_FILE.pdf
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Q: what is operating temp range for thi unit and the Ultra 105
Asked by 15 years ago
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Verified Reply- PexSupply StaffThis boiler operates between 50°F and 180°F.
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Q: Is this available in a propane model?
Asked by 15 years ago
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Verified Reply- PexSupply StaffThis unit includes a propane conversion kit.
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Q: can i use this boiler for domestic hot water and radiant heat with out storage tank
Asked by max 15 years ago
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Verified Reply- PexSupply StaffIn order to use this boiler for domestic hot water, you will need an indirect water heater as well. On its own, the boiler will not work for both heat and domestic hot water.
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Q: how much does this boiler weight
Asked by ray 16 years ago
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Verified Reply- PexSupply StaffThis boiler weighs approximately 193 pounds.
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Q: Can this boiler or the 230 be use for radiant floor heating and baseboard heating with the same or different zone at the same time?
Asked by 16 years ago
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Verified Reply- PexSupply StaffYes, this boiler and the 230 can be used for radiant floor heating and baseboard heating. You would need to use different zones. Yes, they can be used at the same time.
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Q: Is this Boiler CSA approved?
Asked by 16 years ago
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Verified Reply- PexSupply StaffYes, this boiler is CSA approved.
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