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Bringing heat and hot water into perfect Balance

Thank you for your interest in the AquaBalance™ high efficiency combination boiler for residential applications. The new AquaBalance™ combi-boiler combines the unmatched reliability of Weil-McLain® with the warmth of high efficiency space heating and the convenience of on-demand domestic hot water. All in one elegant, affordable and space-saving package. The AquaBalance boiler exceeds ENERGY STAR® certification requirements at 94.4% annual fuel utilization efficiency (AFUE) built with the latest stainless steel, titanium-infused, heat exchanger technology. Additional features and benefits include compact design, multiple venting options, reliable Honeywell® boiler controls with digital display, quiet operation and contractor-friendly access to panels, making installation and servicing clean and easy. Contractors and homeowners alike will appreciate the simple, user-friendly controls and the unit’s aesthetically pleasing design. With great value at an affordable price, rest easy knowing that the design and reliable operation has passed the Weil-McLain gold standard. Achieve balance with the AquaBalance combi-boiler.


If you’d like to be contacted by a Weil-McLain sales representative in your area regarding this product, please provide your information below.

15 + 8 =


Balancing space. Balancing lives.


• 94.4% annual fuel utilization efficiency (AFUE) – low fuel usage, saves energy
• Natural or Propane (LP) gas operation – factory shipped as NG, optional LP conversion kit
• Compact design – increases placement options
• Heavy gauge insulated jacket – provides quiet operation
• 10-to-1 turn down ratio – precisely matches minimal energy usage to the immediate system need
• Low NOx rated – low emissions level achieved South Coast certification
• Single tube, large diameter, ASME certified 316L Stainless Steel heat exchanger
• Pre-wired, plug-in ready electrical design
• Contractor friendly removable sides – makes service clean and easy
• Wall mounting bracket and hardware
• Internal 3-speed Grundfos circulator
• Reliable Honeywell® boiler controls with digital display
• Commercial grade 120V power cord with 3 prong plug
• Unique 3-in-1 vent adapter – approved to accept PVC, CPVC, SS or PP vent materials
• Multiple vent options – direct vent with 2 pipes or concentric, through sidewall or roof
• Internal condensate trap
• 24VAC thermostat relay
• Water treatment – inhibitor and test kit
• Peace of mind warranty

Efficiency and technology that exceeds the standard.

When you choose the AquaBalance™ gas combination boiler (combi), you’re assured energy efficiency that meets the rigorous standards of all Weil-McLain boilers. It’s a level of efficiency that earns ENERGY STAR® rebates and doesn’t compromise on performance. You’re also benefitting from the industry’s latest stainless steel, titanium-infused, heat exchanger technology.

Now add in the capability to meet homeowners’ everyday needs. AquaBalance’s heating capacity keeps every family toasty. And with a full capacity of 155,000 BTU input, AquaBalance has plenty of power for whole house domestic water heating. It provides a constant supply of hot water by producing up to an impressive 4 gallons per minute (GPM at 70°F rise).

By making the switch from a separate boiler and hot water tank to the AquaBalance combi-system, the contractor installation process is streamlined. Fewer pipes and less connection points translate into less time. With AquaBalance, the whole system is up and running quickly.

Once AquaBalance is installed and operating, contractors and homeowners alike will appreciate the simple, user-friendly controls and the unit’s aesthetically pleasing design. Rest easy, knowing that the design and reliable operation has passed the Weil-McLain
gold standard.

Here’s one more thing that makes AquaBalance easy to like: a great value at a very affordable price. It will have a calming effect.



• Factory tested
• Stainless Steel heat exchanger
• Mounting bracket and hardware
• Spark ignition
• Outdoor sensor
• Honeywell control
• T & P gauge

• 3-prong power cord
• Water treatment inhibitor/test kit
• Condensate drain
• Relief valve
• 3-in-1 Vent adapter
• Low NOx SCAQMD compliant
• Flat plate heat exchanger
• 3-speed circulator

• Propane conversion kit
• Concentric vent kit
• Condensate neutralizer