NTI Trinity Lx500
The NTI Trinity Lx500 is the entry of the pure-commercial Lx class: 100 to 500 MBH input at a published 94% AFUE, in a 320 lb floor-standing boiler with 2" water connections and 4" venting to 100 ft.
Key figures
- Max input
- 500 MBH
- Max CSA output
- —
- AFUE
- 94 %
- Min input
- 100 MBH
Input is gas energy consumed; output is heat delivered. Never size from input alone.
NTI Trinity Lx500 in practice
The Lx500 crosses into NTI's light-commercial heartland: 100 to 500 MBH input, floor-standing only, weighing 320 lb with 2" NPT female water connections and a 3/4" NPT male gas connection. NTI's page prints 94% AFUE, while its I&O manual rates sizes from 500 MBH by combustion efficiency (95%) and thermal efficiency (94%) instead of DOE AFUE.
The 100 MBH minimum fire and 4" venting to 100 ft per side set the planning frame: this is a boiler for buildings with real plant demand — multi-suite hydronic systems, commercial spaces and process loads — sized by calculation rather than by house area. It keeps the Lx line's easy-to-clean stainless heat exchanger and touchscreen cascade management.
Best suited to
- Light-commercial hydronic plants with loads between 100 and 500 MBH
- Multi-suite buildings consolidating heating plant into one fire-tube boiler
- Projects wanting cascade-ready touchscreen control with easy heat-exchanger cleaning
Applicability and support
- Model number
- Lx500
- 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 NTI Boilers. Units are shown with every value; notes flag conflicting sources or missing figures.
| Specification | Value | Note |
|---|---|---|
| Input | ||
| Input, minimum | 100 MBH | Per the NTI product page. |
| Input, maximum | 500 MBH | Per the NTI product page. |
| Efficiency | ||
| Efficiency (AFUE) | 94 % | Product-page figure; the I&O manual rates sizes from 500 MBH by combustion (95%) and thermal (94%) efficiency rather than AFUE. |
| Domestic hot water | ||
| Domestic hot water | Heating-only; pair with an indirect tank or separate water heater | |
| Venting and air | ||
| Max. equivalent vent length | 100 ft | 4" pipe per side; maximum equivalent run per the NTI product page. |
| Physical and connections | ||
| Weight | 320 lb | Per the NTI product page. |
| Water connections | 2" NPT female | Per the NTI product page. |
| Gas connection | 3/4" NPT male | Per the NTI product page. |
| Operating limits and other | ||
| Fuel | Natural gas or propane | NTI publishes LP conversion instructions for this series. |
Manuals
- Trinity Lx 150–800 I&O Manual, 99986573, V.2024-06-2899986573 · 2024-06-28
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Frequently asked questions
Why does the Lx500 show AFUE on the page but different ratings in the manual?
The product page prints 94% AFUE. The I&O manual gives DOE AFUE only up to 400 MBH and rates the 500 and larger sizes by combustion (95%) and thermal (94%) efficiency.
Is the Lx500 a residential boiler?
NTI lists the Lx for commercial applications and also mentions smaller sizes for residential use; from the 500 up, the line is light-commercial oriented.
What are the Lx500's connections?
2" NPT female water connections and a 3/4" NPT male gas connection, with 4" venting to 100 ft per side per the NTI product page.
Questions about the NTI Trinity Lx500?
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.
Compare and explore
- NTI Trinity Lx400 vs Lx500Comparison
- NTI Trinity Lx500 vs Lx600Comparison
- NTI Trinity Lx150Same series
- NTI Trinity Lx200Same series
- NTI Trinity Lx300Same series
- NTI Trinity Lx400Same series
- NTI Trinity Lx600Same series
- NTI Trinity Lx700Same series
- NTI Trinity Lx800Same series
- Trinity Lx series hub
- Buying guide
Sources and verification
- NTI — Trinity Lx Series product page · accessed September 7, 2026
- Trinity Lx 150–800 I&O Manual, 99986573, V.2024-06-28 · 99986573 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.