Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
Both the Smith GVX-70 and the Smith GVX-105 belong to the Smith Cast Iron Boilers GVX Series (discontinued) line of non-condensing boilers. The Smith GVX-70 is rated 70 MBH input, 58 MBH gross output and 82.1% AFUE, and the Smith GVX-105 is rated 105 MBH input, 87 MBH gross output and 82% AFUE. Smith GVX-105 lists 35 MBH more input than Smith GVX-70 (105 MBH against 70 MBH). Smith GVX-70 carries the higher published AFUE at 82.1%, against 82%.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Smith GVX-70 | Smith GVX-105 |
|---|---|---|
| AGA input (as printed) | 70 MBH | 105 MBH |
| DOE heating capacity | 58 MBH | 87 MBH |
| Net I=B=R water rating | 50 MBH | 76 MBH |
| AFUE | 82.1 % | 82 % |
| Venting | Optional power vent (GVX model) per BSG-10; no per-size vent table printed | Optional power vent (GVX model) per BSG-10; no per-size vent table printed |
| Fuel | Natural gas or propane | Natural gas or propane |
Published ratings: the Smith GVX-70 is rated 70 MBH input, 58 MBH gross output and 82.1% AFUE; the Smith GVX-105 is rated 105 MBH input, 87 MBH gross output and 82% AFUE. Smith GVX-105 lists 35 MBH more input than Smith GVX-70 (105 MBH against 70 MBH). Smith GVX-70 carries the higher published AFUE at 82.1%, against 82%.
Both records print the same venting (Optional power vent (GVX model) per BSG-10; no per-size vent table printed) and fuel (Natural gas or propane), per the cited sources.
Smith Cast Iron Boilers
The Smith GVX-70 is a discontinued residential cast-iron water boiler rated 70 MBH AGA input with 58 MBH DOE heating capacity, 50 MBH net I=B=R and 82.1% AFUE, offered with an optional power vent.
Smith Cast Iron Boilers
The Smith GVX-105 is a discontinued residential cast-iron water boiler rated 105 MBH AGA input with 87 MBH DOE heating capacity, 76 MBH net I=B=R and 82% AFUE, offered with an optional power vent.
The Smith GVX-105 lists 105 MBH, against 70 MBH on the Smith GVX-70, per the cited documentation.
The Smith GVX-70 carries the higher published AFUE at 82.1%, against 82%.
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.