Navien NHB-150H
The Navien NHB-150H is the largest NHB-H compact boiler: 10 to 150 MBH input at 95.0% AFUE with 15:1 turndown per the quick facts, delivering the most heating of any 23.8-inch-tall boiler in the series.
Key figures
- Max input
- 150 MBH
- Max CSA output
- —
- AFUE
- 95 %
- Min input
- 10 MBH
Input is gas energy consumed; output is heat delivered. Never size from input alone.
Navien NHB-150H in practice
The NHB-150H tops the compact NHB-H line at 150 MBH of input — 10,000 to 150,000 BTU/h — while keeping the short 23.8 in cabinet and the 80 lb weight of the NHB-110H. Navien's quick facts list a 15:1 turndown for this model, the widest in the series, which lets it span from modest shoulder-season loads to large-homes winter peaks.
It remains a heating-only boiler with domestic hot water from an indirect tank or a separate appliance, rated 95.0% AFUE with 1" NPT heating connections and a 3/4" NPT gas connection. Like the rest of the NHB-H series it vents in 2" or 3" PVC to 65 or 150 equivalent feet and runs on 12 to 30 psi system pressure, per the installation manual.
Best suited to
- Larger detached homes whose heat-loss calculation approaches 150 MBH
- Homes wanting a full-size heating input inside a compact, short cabinet
- Projects pairing a 150 MBH boiler with a high-recovery indirect tank
Applicability and support
- Model number
- NHB-150H
- Canadian availability
- available
- Production status
- current
- ROMA supplies
- Confirmed at consultation
- ROMA services
- Confirmed at consultation
- Warranty
- Not verified
Where ROMA provides on-site service
On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.
Specifications
Published specifications
Values as published by Navien. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Heating input, minimum | 10 MBH | Space-heating input. |
| Heating input, maximum | 150 MBH | Space-heating input. |
| Efficiency | ||
| Efficiency (AFUE) | 95 % | 95.0% AFUE per the installation manual. |
| Domestic hot water | ||
| Domestic hot water | Heating-only boiler; domestic hot water via an indirect tank or separate appliance | |
| Venting and air | ||
| Venting | PVC, CPVC or approved polypropylene; 2" or 3" | Canada: plastic venting must meet ULC S636 where required. |
| Max. equivalent vent length, 2" | 65 ft | |
| Max. equivalent vent length, 3" | 150 ft | |
| Physical and connections | ||
| Weight | 80 lb | 36 kg; per the installation manual. |
| Width | 17.3 in | |
| Height | 23.8 in | |
| Depth | 12.8 in | |
| Gas connection | 3/4" NPT | |
| Heating water connections | 1" NPT | |
| Operating limits and other | ||
| Fuel | Natural gas or propane | Separate Navien ratings per fuel. |
| Altitude rating | 10,100 ft | Per installation manual. |
| System water pressure | 12 – 30 psi | |
Manuals
Alerts documented for this model
Frequently asked questions
Is the NHB-150H bigger than the other NHB-H models?
The cabinet is identical at 17.3 x 12.8 x 23.8 in and the weight matches the NHB-110H at 80 lb; only the firing range is larger (10 to 150 MBH).
What turndown does the NHB-150H have?
Navien's quick facts list 15:1 turndown for the NHB-150H. Note that one Navien technical data sheet misprints its minimum as 15,000 BTU/h; the installation manual, quick facts and product page agree on a 10,000 BTU/h minimum.
Can the NHB-150H supply domestic hot water?
Not by itself. It is heating-only, so domestic hot water is handled by an indirect tank or a separate appliance connected to the system.
Questions about the Navien NHB-150H?
Describe what the boiler is doing and get a straight answer about the next step.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
- Navien Canada — NHB-H series · accessed September 7, 2026
- NHB-H Installation and Operational Manual (EN) · accessed September 7, 2026
- NHB-H Service Manual, Ver 1.00 (July 2023) · Ver 1.00 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.