Viessmann

Viessmann is a German manufacturer of heating, climate control and refrigeration systems. Viessmann caters to the upper end of the market and has in the past been known for making very reliable products.

Viessmann

Basic information
Founded	1917
Type	GmbH & Co KG
Industry	Heating and refrigeration systems
Official website	https://www.viessmann.de

Consumer-impact summary

Business Model Concerns

• Forced obsolescence: Viessmann remotely deactivated existing LAN interfaces in heating systems, requiring customers to purchase inferior replacement hardware.
• Paywalled data access: Users must pay a subscription to access real-time data from devices they own, despite the data being collected automatically.
• Costly repairs: The company replaces entire logic boards instead of offering component-level repairs, inflating costs unnecessarily.

User Freedom Issues

• Loss of functionality: Customers are forced to accept reduced performance (infrared/WiFi) after LAN interface deactivation.
• Restricted data access: Full control over owned devices is limited unless users pay additional fees.

Incidents

This is a list of all consumer-protection incidents this company is involved in. Any incidents not mentioned here can be found in the Viessmann category.

Remote Deactivation of LANCard (March 2025)

In March 2025, customers were informed that the integrated network interface that was purchased with the heating solution would be deactivated and would cease to function, citing that the warranty period had elapsed on the affected products. Affected customers should buy a different interface for remote control called a "Vitoconnect", which does not offer equivalent functionality. Viessmann claimed that the speed of the LAN interface was insufficient, while the proposed new device relies on signnificantly slower and less reliable infrared communication and WiFi.

Making users buy back their own data (????)

Kuketz Forum user Galaga cites conversations with their heating technician claiming that Viessmann devices send data to the manufacturer's servers over WiFi at very high frequency. Users can then see the data inside their apps with an artificially imposed rate limit. If a user wants full access to their data in real time, they have to pay for a subscription service to get access to the status information for devices they legally own and paid for.

Not offering component-level repairs

The manufacturer usually does not repair logic boards, but only replaces them when they fail (even if it is just a 5 ct component) at costs of several hundred to a thousand Euros per board, making many repairs unnecessarily cost prohibitive, leading people to replace entire heating installations even when it wouldn't be necessary.

Products

This is a list of the company's product lines with articles on this wiki.

• Example product line one (release date): Short summary of the product's incidents.
• Example product line two (release date):

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See also

Link to relevant theme articles or companies with similar incidents.

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