Scheduled Delivery to Ashburn
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Scheduled delivery to your door.
A scheduled delivery is available only Monday - Friday during normal business hours and used for heavy and oversized items (large TVs, large furniture and large appliances). This service includes delivery to the main entrance or garage (but does not include stairs). This service does not include unpacking, plugging in, installation or debris removal.

Note: Scheduled delivery services are available to most of the contiguous United States (available in parts of Alaska and Hawaii). Call 888-228-5800 for more information.
Discontinued Product
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Weil-McLain Ultra Series 3-UE Gas Boiler - UG-399

Abt Model: ULTRA399
This product is no longer available.

Product Details

Energy Star Rated - Yes

Weil-McLain Ultra Series 3-UE Gas Boiler, Model ULTRA399


  • 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
  • U-Control gives you the power for easy set-up and maintenance
  • Modulates with 5 to 1 turn-down ratio capability
  • 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


  • A.G.A. Input (MBH): 399
  • DOE Heating Capacity (MBH): 365
  • Net I=B=R Ratings (MBH): 317
  • Min. Vent Size: 4in. PVC/CPVC
  • Annual Fuel Utilization Efficiency (AFUE): 91.7%

Approximate Weight:

  • Shipping: 297 lbs

Warranty Information:

  • Manufacturer Warranty (authorized online retailer): 5 Years Parts and Labor
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Key Features
Gas Fired Water Boiler With Cast Aluminum Heat Exchanger/ Venturi Mixing Body/ Designed To Operate In Low Temperature Condensing Applications/ Outdoor Reset And Domestic Hot Water Priority Standard/ Negative Regulated Gas Valve/ Modulates With 5 To 1 Turn-Down Ratio Capability/ Variable Speed Motor/ High Grade Stainless Steel Burner/ 399 A.G.A. Input (MBH)/ 365 DOE Heating Capacity (MBH)/ 91.7 Percent Annual Fuel Utilization Efficiency (AFUE)/ Bisque Finish
More reasons to buy the Weil-McLain UG-399 from Abt Electronics
  • is an authorized dealer (Learn More).
  • The Weil-McLain UG-399 is Brand New.
  • The Weil-McLain UG-399 Ships in a Factory Sealed Box.
Fuel TypeGas
Gallon Capacity (cu.ft.)2.1
Height (inches)47.75"
Energy Star QualifiedNo
Delivery is subject to reasonable access to the area without damaging the purchaser's property or the product, or jeopardizing the safety of the delivery personnel.
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