Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The B2TA 35 and B2TB-125 are consecutive generations of the Vitodens 222-F combi with the same printed 19-125 MBH input range, the same 26.5 USG (100 L) DHW tank and the same 3.3 USG/min continuous draw and 60 USG ten-minute peak at a 70°F rise. The newer B2TB-125 raises AFUE from 93.3% to 95% and weighs 302 lb against the B2TA 35's 282 lb.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Viessmann Vitodens 222-F B2TA 35 | Viessmann Vitodens 222-F B2TB-125 |
|---|---|---|
| CSA input, minimum (NG/LPG) | 19 MBH | 19 MBH |
| CSA input, maximum (NG/LPG) | 125 MBH | 125 MBH |
| Efficiency (AFUE) | 93.3 % | 95 % |
| Weight | 282 lb | 302 lb |
| Integrated DHW tank | 26.5 USG (100 L) | 26.5 USG (100 L) |
| Continuous DHW draw at 70°F rise | 3.3 USG/min | 3.3 USG/min |
| Maximum DHW draw over 10 minutes | 60 USG | 60 USG per 10 minutes |
| Domestic hot water | Combi: space heating and DHW with an integrated storage tank | Combi: space heating and DHW with an integrated storage tank |
Both models are floor-standing 222-F combis with an integrated 26.5 USG (100 L) stainless steel DHW tank and a printed 19-125 MBH NG/LPG input range. DHW figures match at a 3.3 USG/min continuous draw and a 60 USG maximum ten-minute draw at a 70°F rise.
The B2TB-125 prints 95% AFUE against the B2TA 35's 93.3%, and it is heavier at 302 lb (137 kg) against 282 lb (128 kg). The B2TB generation also carries the discontinuation notice on Viessmann Canada's product page, which recommends the Vitodens 200-W B2HE series for new purchases.
Both fall outside the current catalogue: the B2TA is documented in the historic manuals, while the B2TB remains in the current manuals library despite the discontinuation notice. The B2TB-125 is additionally covered by the heat-exchanger replacement safety notice for units built September 1, 2014 to April 25, 2017.
Viessmann
The Vitodens 222-F B2TA 35 is the larger of the two earlier-generation 222-F combis: 19 to 125 MBH NG/LPG input at 93.3% AFUE with an integrated 26.5 USG (100 L) DHW tank and a 3.3 USG/min continuous draw at a 70°F rise.
Viessmann
The Vitodens 222-F B2TB-125 is the discontinued floor-standing combi boiler of Viessmann Canada's 222-F series: 19 to 125 MBH input at 95% AFUE with an integrated 26.5 USG (100 L) DHW tank. Owners should check their serial against the heat-exchanger safety notice.
Yes — both print a 3.3 USG/min continuous draw and a 60 USG ten-minute peak at a 70°F rise from an integrated 26.5 USG (100 L) tank.
The B2TB-125, at 95% AFUE against the B2TA 35's 93.3%.
No. The B2TB page states the series has been discontinued in Canada and recommends the Vitodens 200-W B2HE; the B2TA is an earlier generation kept in the historic manuals.
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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.