Description
The Navien NHB-55H Indoor High Efficiency Condensing Heating Boiler is a compact, high-performance solution designed for modern home heating systems. With dimensions of just 17.3" W x 23.8" H x 12.8" D, it’s ideal for space-saving, wall-hung indoor installations. This unit features stainless steel primary and secondary heat exchangers, ensuring long-term durability and optimal energy transfer. It supports both natural gas and propane, with electronic ignition and a forced draft direct vent system. Venting options include 2" PVC up to 65 feet or 3" PVC up to 150 feet, offering flexible installation configurations. The boiler operates at a natural gas manifold pressure of -0.11" WC and uses a ¾" NPT gas inlet connection, while drawing less than 10 amps of power.
Engineered with multiple integrated safety features such as a flame rod, ignition operation detector, gas valve operation monitor, and high-limit sensors for water and exhaust temperature, the NHB-55H offers reliable, worry-free heating. Its temperature setting range of 86–140 °F (30–60 °C) meets a variety of home comfort needs, while advanced venting systems ensure safe and efficient operation. With its cold rolled carbon steel casing, quiet operation, and energy-efficient design, the Navien NHB-55H is a smart, eco-conscious investment for homeowners seeking performance, longevity, and peace of mind in their home heating system.
Features:
- High efficiency condensing
- Dual stainless steel heat exchangers
- SCH40, 2" venting up to 65'
- 3" venting up to 150'
- TDR up to 7:1
- Built-in zoning control
- Smart controls LCD display, quick dial wheel & Setup Wizard
Dimensions:
-
17.3" W x 23.8" H x 12.8" D (43.9cm W x 60.5cm H x 32.5cm D)
Input:
| Model | NHB-55H |
|---|---|
| Range | 8,000 - 55,000 BTU/h (2.34 - 16.12 kWh) |
| TDR | 7:1 |
Ratings:
Navien Condensing Boiler Space Heating Ratings |
||
|---|---|---|
| Model1 | NHB-55H | |
| Heating Input | Min | 8,000 BTU/h (2.34 kWh) |
| Max | 55,000 BTU/h (16.12 kWh) | |
| Heating Capacity2 | 51,000 BTU/h (14.94 kWh) | |
| Net AHRI Rating, Water3 | 44,000 BTU/h (12.89 kWh) | |
| AFUE2, % | 95.0 | |
1) Ratings are the same for Natural Gas models converted to Propane use.
2) Based on U.S. Department of Energy (DOE) test procedures.
3) The NET AHRI Water Ratings shown are based on a piping and pickup allowance of 1.15. Consult Navien before selecting a boiler for installations having unusual piping and pickup requirements, such as intermittent system operation, extensive piping systems, etc.
Specifications:
| Item | NHB-55H | |
|---|---|---|
| Dimensions | 17.3" W x 23.8" H x 12.8" D (43.9cm W x 60.5cm H x 32.5cm D) | |
| Boiler weight | 73 lbs (33.1 kg) | |
| Installation location | Indoor wall-hung | |
| Venting type | Forced draft direct vent | |
| Max Vent Length |
2" PVC venting up to 65', 3" up to 150' |
|
| Ignition | Electronic ignition | |
| Natural gas supply pressure (from source) | 3.5 " WC to 10.5 " WC (0.87 kPa to 2.61 kPa) | |
| Propane gas supply pressure (from source) | 8 " WC to 13.5 " WC (1.99 kPa to 3.36 kPa) | |
| Natural gas manifold pressure | -0.11 " WC (-0.027 kPa) | |
| Propage gas manifold pressure | -0.11 " WC (-0.027 kPa) | |
| Connection sizes | Gas inlet | 3/4" NPT (male) |
| Power Supply | Main supply | 120V AC, 60Hz |
| Maximum power consumption | Less than 10A | |
| Materials | Casing | Cold rolled carbon steel |
| Heat exchangers |
Primary and secondary heat exchangers: stainless steel |
|
| Venting | Exhaust | 2" or 3" PVC, CPVC, approved polypropylene (see installation manual for more details) 2" or 3" special gas vent type BH (Class III, A/B/C) |
| Intake | 2" or 3" PVC, CPVC, polypropylene 2" or 3" special gas vent type BH (Class III, A/B/C) | |
| Vent clearances | 0" to combustibles | |
| Safety Devices | Flame rod, APS, gas valve operation detector, ignition operation detector, water temp high limit switch, exhaust temp high limit sensor, Vent Installation Detector (VID) | |
| Temperature setting range | 86 - 140 °F (30 - 60 °C) | |
| Normal | 100 W | |
| Standby | 4 W | |
| Anti-frost | 114 W | |
| External pump | < 150 W, 1.5 A W | |
| Fuse | 5.0 A | |
| Materials | Casing | Cold rolled carbon steel |
| Heat exchangers |
Stainless steel |
|
| Safety Devices | Flame rod, APS, VID (vent installation detector), ignition operation detector, water temperature high limit switch, power surge fuse | |
Warranty:
| Product | Labor | Parts | Heat Exchanger |
|---|---|---|---|
|
Residential* |
1 Year | 5 Years | See table below |
|
Commercial |
1 Year | 3 Years | See table below |
Videos:
FAQ:
1)What is a boiler?
A boiler is a heating appliance that is used to heat water, which is then circulated throughout a piping system in a building. The heated water passes through some form of emitter, which will transfer the heat from the water into the building. The cooler water then returns to the boiler to be reheated. A boiler can be designed to heat the water using a variety of different energy sources, including natural gas, liquid propane, fuel oil, or electricity.
2)How does a boiler work?
A boiler is a relatively simple appliance, but will always include a few key components - a heat exhanger, burner, circulator (aka: pump), and some type of control system. When the building where the boiler is installed cools off, a control will tell the boiler to start. The pump (or pumps) will turn on to begin circulating water through the boiler and the building, and the burner will ignite to heat the water. The boiler control will operate to maintain the outgoing water at the temperature required for the application. As the heated water passes through the building, the rooms will warm up to a point where the control will turn the boiler off.
3)How long does a boiler last?
There are many factors that can affect the lifespan of a boiler, such as how well the unit is maintained, the water quality passing through the unit, and how well the system is designed to work with the boiler. Most Navien boilers have a 10-15 year residential warranty (depending on the unit). So a well maintained boiler in a properly designed and installed system could be expected to last up to 20 years or longer in some cases.
4)How do I turn on a boiler?
The operation of the boiler will be controlled by either a thermostat (or mulitple thermostats), or some type of boiler or building control system depending on the design. The Navien boilers have a power button on the front control panel to disable the operation of the boiler if necessary. Installing and service contractors also have access to a service switch inside the cabinet to shut off power to the boiler when needed.
5)How do I bleed a boiler?
Air in a boiler system can cause issues with overheating or preventing the pumps from being able to circulate water. All Navien boilers ship with an automatic air vent, which is typically mounted at the top of the boiler. The air vent can be used to purge air from the boiler (or bleed air) during the initial fill. Every boiler system requires an air eliminator to be installed in the piping system which will remove any remaining air as the water passes through.
6)How do I clean a water boiler?
To clean the outside of the boiler cabinet, a soft dry cloth can be used to wipe down the cabinet. Internal components should only be serviced by a qualified contractor.
7)How do I drain a boiler?
Water should only be drained from a boiler for service, or if the boiler will be turned off for an extended time frame and the system exposed to freezing temperatures. Generally, the boiler will have a drain valve or valves installed in the piping system below the boiler. Prior to draining, power must be turned off to the boiler and the drain valves can be opened. Opening a valve above the boiler may be required to allow the water to drain properly. Consult with a qualified contractor prior to, or if the boiler requires draining.
7)What is a condensing boiler?
A condensing boiler is designed to operate at a higher efficiency than a non-condensing boiler. This is achieved by using a heat exchanger that will transfer more heat from the exhaust into the water to be used to heat the structure. One of the by-products of a gas burner is water vapor, and when enough heat is removed from the exhaust that water vapor condenses inside the heat exchanger. The benefits of a condensing boiler are higher efficiency (operational cost savings), lower heat loss in the mechanical room, and lower exhaust temperatures.
8)What size boiler do I need?
Boilers are sized based on the amount of heat they can put out, measured in BTU's (British Thermal Units). The size of the boiler is determined by calculating the heat loss of the building, which is based on the size of the structure, the insulation value of the surfaces, and the door and window sizes. The size of the boiler required must exceed the heat loss to satisfy the system. A qualified contractor can perform a heat loss and help recommend a proper boiler size.
Order Confirmation:
Upon placing your order, you will promptly receive an email confirmation. Subsequently, we will conduct a thorough inventory check to ensure all items are in stock and available for immediate shipment. If your order aligns with the advertised delivery timeframe, we will promptly process it for shipment to our warehouse. In cases where the expected delivery time extends beyond the advertised timeframe, we will reach out to you via email and/or phone for confirmation.
Order Shipment:
Within one business day of your item being shipped, you will receive an email confirmation containing a tracking number. If you do not receive tracking information within six business days of placing your order, please don't hesitate to get in touch with us for assistance.
Estimated Time of Arrival:
Our typical delivery timeframe ranges from 2 to 10 business days. Custom-made products generally require 3 to 5 weeks for delivery. If the expected delivery date for your order would fall outside of the advertised 2-10 business day time frame, our customer service team will contact you to ensure your agreement with the revised timeline.
Covered Areas:
Please note that all estimated delivery dates and shipping costs advertised on our website apply exclusively to the Contiguous United States. For inquiries regarding shipping to Hawaii or Alaska, kindly reach out to our customer service team. While we do not offer direct shipping to Canada, we are more than willing to ship your order to the freight carrier of your choice.
Damages:
It is very important that you inspect the packaging of your items when they arrive and check if you received all boxes listed on the delivery receipt. If you notice any damage or shortage of packages, you must make note of it on the bill of lading, take pictures, and refuse delivery. Your note should say "refused due to damage". You must also take photos of all sides of the box and send them to us within 2 days. If there are no damages visible before opening the box, you must note "subject to further inspection may contain concealed damage". If you notice any damage after receiving the delivery, do not throw the box away, and contact us with the photos. After we receive information from you about the refused delivery or concealed damage, we immediately initiate a claim with the shipping company or with the manufacturer. After the claim is fully processed, we ship all replacements at absolutely no cost to you.
Cancellations & Refunds:
We offer free order cancellations before the shipping label or Bill of Lading is generated, or prior to the commencement of production for custom orders. Please note that custom-made items are not eligible for refunds once production has begun. To be eligible for a return, the item must be unused and in its original condition, with all packaging intact and in perfect condition. Orders delivered outside of the United States are not eligible for refunds. If your order arrives damaged, please refer to the "Damages" section. Our refund policy extends for 30 days. If 30 days have elapsed since your purchase, regrettably, we cannot process a refund. Prior to returning an item, please contact us to discuss shipping details. All refunds will be credited to the original credit card or PayPal account used for the purchase, within two days of receiving the returned items at our warehouse.
Please contact sales@belleflame.com for any questions regarding shipping time.
At Belleflame, we're committed to providing our customers with the best prices on the market. That's why we offer a 110% best price guarantee. If you find a better deal on the same product somewhere else, just let us know and we'll beat it by an additional 10%.
We believe that shopping should be easy, convenient, and most importantly, affordable. That's why we work hard to bring you the lowest prices on the products you love. But if you do happen to find a better deal elsewhere, we'll go the extra mile to make sure you get the best deal possible.
Here's how it works:
- Find a lower price on the same product from another retailer.
- Contact us with the details of the offer, including the website or store name, product name, and price.
- We'll verify the price and beat it by an additional 10%.
It's that simple! Our 110% best price guarantee ensures that you'll always get the best deal possible when you shop with us. So, why wait? Start shopping now and experience the difference of shopping with Belleflame.
At Belleflame, we believe that shopping should be simple, stress-free, and most importantly, enjoyable. That's why we work hard to bring you the best products, prices, and customer service in the industry.
Here are just a few reasons why you should choose us:
- Wide Selection of Products: We offer a vast selection of top-quality products from the leading brands in the industry. No matter what you're looking for, we have something for everyone.
- No Sales Tax, no Hidden Fees: just the lowest prices on the market. When you shop with us, you can rest assured that the price you see is the price you'll pay. No matter where you live, you can enjoy tax-free shopping with us.
- Fast and Free Shipping: We understand that you want your products as soon as possible. That's why we offer fast and free shipping on all orders.
- Easy Returns: We want you to be completely satisfied with your purchase. If for any reason you're not happy, just let us know and we'll make it right.
Guaranteed Secure Checkout
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
You may also like
Recently viewed
Let customers speak for us
INSTALLED...EVERYTHING IS WORKING JUST AS EVERYONE WANTED AND EXPECTED!! 👍👍🍸🍸
Home I just got and I want to get updated Empire heating system for this house. Before sold out!
So yeah my last one was a Empire 35k buys so that’s why I’m getting it for my replacement from my previous purchase Empire. In the 1980s it was from a old house that I bought from somebody!
This stove is sold at an excellent price! Took a few weeks to come in, but for the price it can’t be matched!
I haven’t installed yet. But they look great . The shipping was done rather well.
Turned out to be the best experience. We did not know much about Belle Flame. Their price for the Buck Homesteader Wood Stove was way lower then competitors so we could not resist going through them. Belle Flame was PERFECT. They answered all our messages within less than an hour or two and are still answering our questions. The stove arrived in 11 days , we are way up North and they are way down South. BTW, we love the stove. Check it out at Knetter's Practical Outdoors.
https://www.youtube.com/watch?v=7YDJRPJT-Qo
The stove is nicer than we expected. Unfortunately we didn’t know about needing a fresh air kit when we selected the pedestal for the stove. Since the stove will be in our basement and below ground this set up is not practical. So a five for the price and shipping. Not sure what we can do about the pedestal at this point. Maybe a one for all the advertising of the pedestal as there is no clear information about needing to add a fresh air kit.
Best price on Bromic heater and prompt delivery into garage. Did everything right!
Product as stated and ship promptly
Great product and no longer smell propane from the fire place. Most likely the valve was faulty on the existing burner I had, but for the great price of a whole new burner unit, I just replaced it all in one job. Simple and done. Sure you could have saved some money doing parts as needed but I wanted once and done.
Great job
Heavy duty and a nice bronze finish. I’m happy with my purchase. It looks like it will be around for many years.
I live in the Upper Peninsula of Michigan, I knew nothing about this company, saw some good reviews for Belle Flame. I received a $1000 off discount from Belle, if I had gone through the other company that I had originally found the wood stove on it would have cost about $1500 more after shipping and tax. That is a big price difference, I had to give Belle Flame a shot. I AM SO HAPPY, I placed my order, the wood stove was here in 11 days, that is amazing! I will be putting a video up on Youtube on my shopping experience through Belle Flame and a review of my Buck Homesteader wood stove I purchased through Belle Flame. I will update with the video link as soon as it is posted.
Thank you Belle Flame for the GREAT experience.
And thank you Lionel for answering all my questions. =)
My new Hearthrite Empire wall mounted propane heater was installed today. I absolutely love it. It looks nice & I like fact that is thermostat regulated. I had one minor problem prior to receiving the heater. When it didn't arrive when expected I started making phone calls & after talking to 3 different people at 3 different locations I found out it had never been shipped. Once we got that straightened out I received it in 3 days. I am glad I chose the Empire heater. Quality built. Thank you Bell flame, Pam
Looks beautiful & works great. Shipping was also excellent & very well packed.
![Iron Strike Montlake 230 Wood Insert - [ML230GL] (30% Tax Credit Qualified)](https://cdn.shopify.com/s/files/1/0591/9912/7740/products/IronStrike-wbin-Montlake230_PD-1136x852-1_70x70.jpg?v=1669994659)