Condensing Gas Boiler

Condensing Boilers

Simply Smart Engineering. Simply Better Home Heating.

When it comes to home heating, it’s all about comfort, convenience and reliability. At Rinnai, we design products that let you experience all three. Our extensive line of Condensing Boilers provides efficient whole-home heating, water heating or both in one advanced system.

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Comforting warmth and soothing hot water. Delivered from one smart system.

Home and water heating. Keeping comfort coming.

Comfort means different things to different people. Whether it’s consistent heat throughout a home, pleasant humidity levels, or continuous hot water, our industry-leading line of Condensing Boilers keeps comfort coming with unparalleled performance.

Improve efficiency - increase comfort: A dvanced s mart system technology includes an outdoor reset sensor that continually adjusts to changing temperatures.

Hot water without interruption: O ur E S eries “ combi” models have the power to deliver whole-house heating and domestic hot water priority for homes with one to two bathrooms.

Wide range of options: Because comfort is such a personal choice, we offer ten models to give you a wide range of quality options for both existing homes and new construction.

Waste not, pay not with superior efficiency.

Conventional heating systems waste energy with significant heat loss vented into the atmosphere. Rinnai Condensing Gas Boilers are designed to recover heat energy that is discharged into the flue and return it to the heat exchanger for maximum efficiency.

Energy-smart performance:Thanks to advanced technology, our condensing boilers have one of the highest AFUEs (Annual Fuel Utilization Efficiency) in the industry.

Consistently comfortable heat: Our modulating gas valve responds to small temperature changes with incremental increases in BTU.

One complete system:Our Condensing Boilers ship with a factory-assembled low-loss header, integrated boiler pump, and pre-programmed outdoor reset sensors. (Factory-assembled low-loss header kit not included with E50C boiler model.)

Efficient warmth: With a fully-modulating boiler pump that uses only as much energy as needed, you will experience a consistent level of warmth throughout your home and steady savings throughout the year.

Enduring quality. Lasting peace of mind.

No one can predict the future, but the past is a good gauge of things to come. Rinnai’s nearly 100 years of superior engineering, safety and quality inspire peace of mind that our boilers will stand the test of time.

The Rinnai tradition of building in quality at every level with a 12-year heat exchanger warranty* ensures many years of comfort and warmth. And our superior technical support for professionals along with durability testing means peace of mind and performance you can trust.

Main features to ensure quality you can trust:

Stainless steel heat exchanger: Our proprietary selfcleaning, down-fired stainless steel heat exchanger has industry-leading performance and durability.

OSS (one-side sealed) construction: This arrangement maintains integrity during heat exchanger expansion and contraction.

Factory-assembled low-loss header kit: Professionals will save time and money with our convenient factory-assembled low-loss leader kit that’s shipped with the model.

Integrated boiler pump:Our boiler pump eliminates the need to size the pump for the boiler loop and keeps a tight rein on energy usage.

** For complete information and details regarding Rinnai’s warranty, please visit

Space to spare, no matter where.

When you’re raising the bar on condensing boiler performance and efficiency, reducing space requirements vs. traditional boilers simply comes with the territory. Rinnai Condensing Boilers can be easily retrofitted in existing homes or installed in new construction.

E Series “combi” models: These compact wall-mounted designs provide heating and hot water in one full package.

Floor-standing Q Premier Series:Enjoy a complete, fully assembled space-saving solution featuring a boiler and tank all-in-one.

Multiple venting options on all models: Our multiple venting options allow for installation in a variety of locations that result in quicker installations and lower labor costs.

Rinnai Condensing Boilers

Unparalleled comfort and efficiency for your home. That’s what you get with our range of economical, reliable and space-saving Rinnai Condensing Boilers. And while a boiler may not be a focal point in your home, its function is of the utmost importance. That’s why the way a Rinnai Condensing Boiler is built sets it apart from other available heating and hot-water options.

1 Gas-Air Mix

2 Combustion of Gas-Air Mix

3 Hot CH Water

4 Flue Gasses

5 Fan and Venturi Assembly

6 Upside-Down Ceramic Burner

7 Stainless Steel Pipes

8 Condensate Outlet



Perfect for replacement or new construction, these all-inone floor-standing boilers deliver high-volume hot water and efficient home heating.


  • The QP130 provides 211 gallons (799 L) in the first hour, while the QP85 provides 141 gallons (534 L) for an abundance of hot water.
  • The space-saving boiler has more than five times less of a footprint than a traditional boiler and indirect tank system.
  • Multiple plumbing and venting options enable easy set-and-connect installation. The boilers come fullyassembled with integrated connections for domestic hot-water recirculation lines, factory-installed low-loss header and expansion tank.
  • The zero-clearance installation design is perfect for remodeling.

* 141,000 output for domestic.

** Based on AHRI testing standard for indirect-fired water heaters.

*** Based on 90° rise.



An outstanding choice for light-commercial applications or any home with a separate indirect hot-water source, our wall-mounted boilers free up valuable floor space while maintaining maximum comfort in your home.


  • The four “S” boiler models deliver energy-efficient home heating and offer an optional 3-way diverter valve to simplify installations that have an indirect tank.
  • Consistent temperature is delivered using a thermostatic mixing valve in our Q175C combi heating/hot-water boiler with an onboard 6.6 gallon (25 L) gallon fully-insulated, indirect tank.
  • There’s no wasted energy with the fully-modulating boiler pump that uses just the BTU needed to meet the immediate demand (The maximum BTU input ranges from 85,000 to 205,000).
  • Installation flexibility allows venting up to a total of 200 feet – 100 feet exhaust and 100 feet intake.



Perfect for homes with 1 to 2 baths, E Series Combi Boilers ensure homeowners won’t have to sacrifice continuous hot water.


  • The space-saving, wall-mounted design integrates the boiler pump and heating expansion tank (Excluding the E50C boiler model).
  • A plate-warming feature delivers faster hot-water.
  • Continuous hot water is available via domestic hot water priority.
  • The design provides increased efficiency to meet your home’s needs, with a maximum BTU heating input from 75,000 to 110,000.
  • A stainless steel domestic hot-water plate heat exchanger creates proven long-lasting durability.
  • The E50C is specifically designed for multifamily applications or smaller single-family homes with up to 1.5 baths with no secondary piping or closely- spaced tees required†

†Not required if the pressure drop in any system loop(s) does not exceed 4.6 of head at 4.5 GPM flow rate.