Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The FTHW100 and FTHW140 are the two smallest heating-only FT Series Wall boilers and are identical in every documented respect except the rating step: 100,000 BTU/h against 140,000 BTU/h as printed on the manual cover (Document 1483C). A heat-loss calculation decides which ceiling the home actually needs.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Laars FTHW100 | Laars FTHW140 |
|---|---|---|
| Maximum input (as printed) | 100 MBH | 140 MBH |
| Fuel | Natural gas or propane | Natural gas or propane |
| Domestic hot water | None built in — heating-only model; hot water comes from a separate tank or water heater | None built in — heating-only model; hot water comes from a separate tank or water heater |
| Error reporting | Two-digit numeric codes with Soft Lock and Hard Lock classes per Section 6.1 of the installation manual | Two-digit numeric codes with Soft Lock and Hard Lock classes per Section 6.1 of the installation manual |
Both models are the same wall-hung condensing heating-only design on the NGTB-900CP control, documented together in the FTHW installation manual (Document 1483C). Both run natural gas as the factory configuration with propane field-convertible, and both report the same two-digit numeric FT code family with Soft Lock and Hard Lock classes — so nothing about servicing or diagnosis changes between them.
The only published difference is the input printed on the cover: 100,000 BTU/h on the FTHW100 versus 140,000 BTU/h on the FTHW140. Because every other documented figure is shared, the choice is purely a sizing question: a home whose room-by-room heat loss fits comfortably under 100 MBH is served by the FTHW100, and a load that approaches 100 MBH or more on a design day points to the FTHW140.
Neither model produces domestic hot water — both are heating-only, so hot water comes from a separate tank or water heater. Homes wanting integrated hot water move to the FTCW combi versions of the same wall series.
Laars Heating Systems
The Laars FTHW100 is the smallest FT Series Wall heating-only boiler: a wall-hung condensing unit rated 100,000 BTU/h on the manual cover, natural gas from the factory with propane field-convertible, on the NGTB-900CP control.
Laars Heating Systems
The Laars FTHW140 is the mid-size FT Series Wall heating-only boiler: a wall-hung condensing unit rated 140,000 BTU/h on the manual cover, natural gas from the factory with propane field-convertible, on the NGTB-900CP control.
They are two size steps of the same wall-hung FT heating-only design, sharing one installation manual (Document 1483C), one control and one code set. The manuals and parts scale with the size, and Laars rates the series at 95% AFUE.
When the heat-loss calculation (plus any recovery load) shows the home can need more than about 100 MBH on a design day. Extra ceiling without a matching load is not an advantage in a modulating condensing boiler.
Yes. Both use the FTHW two-digit numeric code family in Section 6.1 of Document 1483C, with each code typed as a Soft Lock or Hard Lock and its own remedy.
A consultation includes a heat-loss review so the size is right the first time.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.