Lochinvar Commercial Boilers: Full Model Lineup and How to Choose the Right One

Searching “Lochinvar” turns up a wide spread of results, because it’s not really one product — it’s a full commercial boiler brand spanning condensing and non-condensing gas-fired lines, outdoor-rated units, and electric boilers, each built for a different job. A mechanical contractor comparing a retrofit replacement against a new high-efficiency install is often looking at two completely different product families under the same brand name. This guide breaks down what Lochinvar actually makes in the commercial space right now, the real distinction between the lines, and how to narrow down which one fits a given application before you spec it.

Condensing vs. Non-Condensing — The Split That Actually Matters

The first fork in the road isn’t model name, it’s combustion type. Condensing boilers extract additional heat from flue gas by cooling it low enough to condense water vapor out of the exhaust, which is what lets them hit higher efficiency than older non-condensing designs — but that also means they need condensate drainage, and they’re generally the right call on new installations or system upgrades where the piping and venting can be designed around them from the start. Non-condensing boilers run hotter flue gas and skip the condensate handling entirely, which is often the more practical choice on a like-for-like replacement in an existing mechanical room where venting, clearances, and piping are already fixed to a non-condensing configuration.

This distinction matters more than the specific model name for a first-pass selection, because it immediately splits Lochinvar’s current commercial lineup into two groups that aren’t really competing with each other — they’re built for different jobs.

Lochinvar’s Current Condensing Commercial Lines

Crest, including Crest with Hellcat combustion technology, is Lochinvar’s flagship commercial condensing gas-fired boiler line. Hellcat refers to the combustion technology used in the newer Crest units specifically — if you’re comparing quotes and see “Crest” on one and “Crest with Hellcat” on another, that combustion technology distinction is worth confirming with your rep, since it affects the specific unit you’re getting, not just a marketing label.

FTXL is Lochinvar’s other current condensing gas-fired commercial boiler line, positioned alongside Crest as a separate product family rather than a smaller version of it.

Knight XL is a condensing gas-fired commercial boiler line that also comes in an Outdoor Knight XL configuration for installations where the unit needs to be sited outside the mechanical room envelope. Crest similarly has an Outdoor Crest configuration. If a project has site constraints that push equipment outdoors — a common issue on retrofit jobs with no more mechanical room floor space — confirming whether the line you want has an outdoor-rated version is worth doing before the rest of the spec gets locked in.

Lochinvar’s Current Non-Condensing Commercial Lines

Power-fin is Lochinvar’s current non-condensing commercial gas-fired boiler line.

Copper-fin II is a separate non-condensing commercial line, and it comes in two combustion configurations: Copper-fin Fan Assisted and Copper-fin Atmospheric. The fan-assisted and atmospheric distinction is about how combustion air is handled, and it’s the kind of detail that matters for matching a replacement unit to existing venting — an atmospheric-vent mechanical room and a fan-assisted/power-vent mechanical room aren’t interchangeable without additional work, so this is worth confirming against what’s already installed rather than assuming.

Lochinvar’s Electric Commercial Lines

Lochinvar also makes commercial electric boilers under a few names: Lectrus, Compact Electric, and a broader Commercial Electric Boiler line. Electric boilers come up most often on projects where gas service isn’t available or isn’t practical to bring to the mechanical room, or where a facility is specifically moving away from combustion equipment — increasingly common on institutional and municipal projects with electrification requirements written into the project scope. If gas access or a decarbonization mandate is part of the picture, this is the product family to be looking at rather than any of the gas-fired lines above.

How to Actually Narrow This Down

Working through a Lochinvar selection in order gets you to the right family fast: first, is this a retrofit into existing non-condensing venting and piping, or a new/redesigned system that can support condensing — that alone splits the lineup in half. Second, is a gas-fired unit viable for this site, or does gas access or an electrification requirement point toward Lectrus, Compact Electric, or the Commercial Electric Boiler line instead. Third, if you’re in condensing gas-fired territory, does the unit need to sit outdoors — which points toward Outdoor Crest or Outdoor Knight XL rather than their indoor counterparts. Only after those three questions are answered does it make sense to get into unit-by-unit sizing and combustion technology comparisons like Crest vs. Crest with Hellcat, or Copper-fin Fan Assisted vs. Atmospheric — those are real distinctions, but they’re the second-pass decision, not the first one.

Watch It In Action

Lochinvar’s own manufacturer channel publishes an official overview, “Introducing CREST Commercial Boiler with Hellcat™ Combustion Technology,” covering the flagship condensing line and what the Hellcat combustion technology actually changes about the unit.

What to Have Ready Before You Order

Once you’ve narrowed down to a line, the fastest path to the correct unit is having the application details ready: whether the install is a retrofit into existing venting or a new system design, available fuel source (gas vs. electric-only site), whether the unit needs to be outdoor-rated, and your required input/output capacity from a heat loss or replacement-load calculation rather than a guess based on the old unit’s nameplate (equipment specified decades ago is very often oversized relative to actual building load today).