Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The B2HA-285 and B2HA-311 are the two smallest models of Viessmann Canada's high-input Vitodens 200-W line, and they are twins below the top of the range: both fire from a 71,000 BTU (21 kW) minimum input, both weigh 194 lb (88 kg) in the same 19 x 21 x 43.5-inch cabinet. The 311 adds 26 MBH of ceiling — 311,000 BTU (91 kW) against 285,000 BTU (83 kW) — and the page labels their efficiency rows differently: 92% AFUE for the 285 versus a 94.5% thermal-efficiency row (ANSI Z21,13/CSA 4.9) for the 311.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Viessmann Vitodens 200-W B2HA-285 | Viessmann Vitodens 200-W B2HA-311 |
|---|---|---|
| Input, minimum (natural gas) | 71 MBH | 71 MBH |
| Input, maximum (natural gas) | 285 MBH | 311 MBH |
| Weight | 194 lb | 194 lb |
| Width | 19 in | 19 in |
| Depth | 21 in | 21 in |
| Height | 43.5 in | 43.5 in |
Viessmann Canada prints a 71,000 BTU (21 kW) minimum input for both the B2HA-285 and the B2HA-311, so at low fire the two wall-hung boilers behave identically. Maximum input is where they part ways: 285,000 BTU (83 kW) on the 285 against 311,000 BTU (91 kW) on the 311.
Weight, cabinet and fuel are shared: both weigh 194 lb (88 kg) and measure 19 x 21 x 43.5 inches (480 x 530 x 1105 mm), and both run on natural gas or liquid propane with no fuel-conversion kit required. The page's technical table also interleaves legacy B2HB rows with the current B2HA rows; only the B2HA figures apply to these two models.
The efficiency rows are not directly comparable because the page labels them differently: it prints 92% AFUE for the B2HA-285 and a 94.5% thermal-efficiency row (ANSI Z21,13/CSA 4.9) for the B2HA-311, with marketing copy elsewhere on the same page citing an 'up to 95% AFUE rating'. The choice between the models therefore rests on the heat-loss calculation: below roughly 285 MBH the smaller unit is enough, and its lower cost is the argument.
Viessmann
The Vitodens 200-W B2HA-285 is the entry size of Viessmann Canada's high-input B2HA line for large homes: 71,000 to 285,000 BTU (21 to 83 kW) of input in a 194 lb wall-hung condensing boiler, with a printed 92% AFUE spec row.
Viessmann
The Vitodens 200-W B2HA-311 is the second size of Viessmann Canada's high-input B2HA line: 71,000 to 311,000 BTU (21 to 91 kW) of input in the 194 lb wall-hung condensing boiler, with a printed thermal-efficiency row (ANSI Z21,13/CSA 4.9) of 94.5%.
No. Both weigh 194 lb (88 kg) and share the same 19 x 21 x 43.5 inch (480 x 530 x 1105 mm) cabinet per Viessmann Canada; only the maximum input differs (285,000 vs 311,000 BTU).
The page prints their efficiency on differently labelled rows: 92% AFUE for the B2HA-285 and 94.5% thermal efficiency (ANSI Z21,13/CSA 4.9) for the B2HA-311, so the two figures are not directly comparable.
When the heat-loss calculation plus indirect-tank recovery needs more than about 285 MBH. Below that, the 285 delivers the same minimum fire in the same cabinet at a lower maximum input.
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 8, 2026. Last updated September 8, 2026. Technical reviewer: not yet assigned.