Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The Luna Duo-tec 60GA is the largest Baxi combi and fires in two printed modes — 164 MBH in central-heating mode and 205 MBH in DHW mode — against the 40GA's single 125 MBH input figure, with 5 GPM versus 3.9 GPM of hot water at a 70°F rise. It moves to a different combustion package (Iron-Chromium stainless steel burner with a brazed plate heat exchanger, three-speed pump) in a deeper 21.5 in, 125 lb cabinet.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Baxi Luna Duo-tec 40GA | Baxi Luna Duo-tec 60GA |
|---|---|---|
| Input (as printed) | 125 MBH | 164 MBH |
| Input, DHW mode (as printed) | — | 205 MBH |
| Efficiency (as printed) | 95% AFUE | 95% AFUE |
| Domestic hot water flow rate (as printed) | 3.9 GPM @ 70°F temperature rise | 5 GPM @ 70°F temperature rise |
| Turndown, central-heating mode (as printed) | 5.5:1 | 5.5:1 |
| Turndown, DHW mode (as printed) | 7:1 | 7:1 |
| Burner / heat exchanger (as printed) | Stainless steel ANSI 316L pre-mixed burner and heat exchanger | Iron-Chromium Stainless Steel Burner and Brazed Plate Heat Exchanger |
| Circulator pump (as printed) | Two-speed modulating pump with built-in air vent | 3 speed, electronically controlled pump |
| Dimensions (as printed, W x D x H) | 17.72"(w) x 13.59"(d) x 30"(h) | 17.75"(w) x 21.5"(d) x 30"(h) |
| Weight (as printed) | 102 lb | 125 lb |
| Vent material (as printed) | Coaxial or two-pipe polypropylene | Coaxial or two-pipe polypropylene |
| Gas type (as printed) | Natural Gas / Propane | Natural Gas / Propane |
Both combis are current Luna Duo-tec products printing 95% AFUE, ENERGY STAR certification, THINK combustion management with GAC and a 5.5:1 central-heating / 7:1 DHW-mode turndown, but the 60GA is the physically different top of the combi line: its page prints '164 MBH Input in CH Mode / 205 MBH in DHW Mode' while the 40GA page prints a single '125 MBH Input' bullet.
Hot water scales with the DHW mode: the 60GA page prints 5 GPM at a 70°F temperature rise against the 40GA's 3.9 GPM. The 60GA also changes hardware — an Iron-Chromium stainless steel burner with a brazed plate heat exchanger and a three-speed, electronically controlled pump replace the 40GA's ANSI 316L pre-mixed burner set with its two-speed pump.
The cabinet grows at the same step: the 60GA prints 17.75 in wide x 21.5 in deep x 30 in high at 125 lb against the 40GA's 17.72 x 13.59 x 30 in at 102 lb. Both vent in coaxial or two-pipe polypropylene and print Natural Gas / Propane. Neither page carries a discontinued banner, so both records are current.
The Baxi Luna Duo-tec 40GA is a 125 MBH wall-hung condensing combi on baxiboilers.com — 95% AFUE as printed, 7:1 DHW-mode turndown and 3.9 GPM @ 70°F temperature rise — modelled from its official current product page.
The Baxi Luna Duo-tec 60GA is a 164 MBH wall-hung condensing combi on baxiboilers.com — 95% AFUE as printed, 7:1 DHW-mode turndown and 5 GPM @ 70°F temperature rise — modelled from its official current product page.
Its official page prints '164 MBH Input in CH Mode / 205 MBH in DHW Mode' — the DHW-mode rating is higher than the central-heating one, and Boilers.ca records both as printed.
5 GPM against the 40GA's 3.9 GPM at a 70°F temperature rise, per the printed page bullets.
No — the 60GA page prints an Iron-Chromium stainless steel burner with a brazed plate heat exchanger, while the 40GA prints the stainless steel ANSI 316L pre-mixed burner and heat exchanger.
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 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.