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Viessmann · Vitocrossal 200 (CM2, GW6B)

Viessmann Vitocrossal 200 CM2-400

The Vitocrossal 200 CM2-400 opens the large CM2 (GW6B) chassis: 287 to 1445 MBH natural-gas input (84 to 423 kW) at 95.1% combustion efficiency and 5:1 turndown, weighing 1495 lb (678 kg).

CurrentSold in Canada

Key figures

Max input
1,445 MBH
Max CSA output
AFUE
Min input
287 MBH
Natural gasPropaneHeating-onlycommercial

Input is gas energy consumed; output is heat delivered. Never size from input alone.

Viessmann Vitocrossal 200 CM2-400 in practice

The CM2-400 is the first of the three large Vitocrossal 200 CM2 models (CM2-400/500/620), which move from the 726–792 lb small chassis to a 1495 lb (678 kg) unit. Its natural-gas input prints from 287,000 to 1,445,000 BTU (84 to 423 kW).

The large models print a slightly different efficiency row: 95.1% combustion efficiency against the small models' 95%, with the same 5:1 turndown. The large chassis is documented by its own service instructions (doc 5546 489 - 15, 05/2021, covering CM2-400/500/620).

As across the series, the CM2-400 uses the Inox-Crossal stainless steel heat exchanger and pre-mix cylinder burner, runs on natural gas or propane with simple electronic conversion, and is controlled by the Vitotronic 300 GW6B, with common venting of up to four boilers and no dedicated boiler pump required.

Best suited to

  • Commercial plants whose load exceeds the small CM2 chassis ceiling
  • Projects needing up to about 1445 MBH of input in one floor-standing unit
  • Plants standardizing on the 400–620 service-manual range

Applicability and support

Model number
CM2-400
Canadian availability
available
Production status
current
ROMA supplies
Confirmed at consultation
ROMA services
Confirmed at consultation
Warranty
Not verified

Where ROMA provides on-site service

On-site service is currently offered in Greater Vancouver, BC, including Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Port Coquitlam, Port Moody, Delta, Langley, Maple Ridge, Abbotsford, Chilliwack, White Rock, Pitt Meadows, Tsawwassen, Anmore, Lions Bay, Belcarra, Bowen Island, Mission. Everything else on this site is reference information you can use anywhere in Canada.

See all service areas

Specifications

Published specifications

Values as published by Viessmann. Units are shown with every value; notes flag conflicting sources or missing figures.

Viessmann Vitocrossal 200 CM2-400 specifications
SpecificationValueNote
Input
Input, minimum (natural gas)287 MBH287,000 BTU (84 kW), per the product page
Input, maximum (natural gas)1,445 MBH1,445,000 BTU (423 kW), per the product page
Efficiency
Combustion efficiency95.1 %Per the product-page efficiency row.
Physical and connections
Weight1,495 lb678 kg
Operating limits and other
Turndown ratio5:1Per the product page.

Frequently asked questions

How does the CM2-400 differ from the CM2-311?

Maximum natural-gas input rises from 1,112,000 to 1,445,000 BTU (326 to 423 kW), the minimum fire rises from 222,000 to 287,000 BTU, and the unit moves from the 792 lb small chassis to the 1495 lb large chassis. The printed efficiency row also rises from 95% to 95.1%.

What efficiency does the CM2-400 print?

95.1% combustion efficiency per the product-page efficiency row, the figure shared by the CM2-400, CM2-500 and CM2-620.

Which service manual covers the CM2-400?

The CM2 service instructions for the 400, 500 and 620 models, doc 5546 489 - 15 dated 05/2021.

Questions about the Viessmann Vitocrossal 200 CM2-400?

Describe what the boiler is doing and get a straight answer about the next step.

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.

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