Technical Service Bulletin

Replacement BCU and HMU units must be configured prior to installation in Vitocrossal 200 CI2

Applies to: Vitocrossal 200, CI2 Series (all models)

Important Disclaimer

The information in this bulletin is intended exclusively for licensed heating contractors, and is NOT intended for the end user. This material is NOT intended to take the place of the information contained in the manuals shipped with the product.

Use of this information by unqualified personnel may result in property damage, personal injury or death.

End users are asked to contact a qualified contractor for all installation and service work. If you need assistance finding a contractor in your area, contact your Viessmann Sales Representative, or use our Contractor Locator.

By hitting "Yes" below you confirm that you have read, understood and agree to this warning, that you are licensed and hold the current, appropriate licences to work on said equipment in the location and/or jurisdiction of installation.

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If a replacement Burner Control Unit (BCU) or Heat Management Unit (HMU) is not configured before it's installed in a Vitocrossal 200 CI2 boiler, then the boiler will display an error and it will not be able to operate. This is by design – these parts need to be configured for a specific boiler before they are installed.

Currently, the configuration process for BCU and HMU units for Vitocrossal 200 CI2 can only be performed using Viessmann's proprietary software "Service Assistant", which is not publicly available. The ViGuide mobile app is not capable of configuring BCU or HMU units for Vitocrossal 200 CI2 at this time.

For this reason, these BCU and HMU parts should not be stocked outside of Viessmann. If a "blank" BCU or HMU is sent to a customer, it will not work in their Vitocrossal 200 CI2 boiler.



Before a replacement BCU or HMU unit is installed in a Vitocrossal 200 CI2 boiler, it must be configured using Viessmann's "Service Assistant" software.

In situations where a contractor needs a replacement HMU or BCU for their Vitocrossal 200 CI2 boiler, they should call Viessmann Technical Support (USA: 844-649-5886 / Canada: 888-484-8643).

For BCU replacements, the Technical Service department will ask for the boiler serial number and the CV2 number from the gas valve of the affected burner. The Technical Service department will then configure a BCU and essentially "marry" the BCU to the gas valve. For HMU replacements, only the boiler serial number is required.

After the Technical Service department configures the BCU or HMU, the parts will be shipped directly to the contractor, ready for installation.


Viessmann Technical Services


Bulletin ID:


Date issued:

January 29, 2024

Updated on:

January 29, 2024

Revision #:


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