How do Viessmann devices communicate with each other? Viessmann devices communicate via the secure Viessmann cloud. Energy Management Related articles Where can I configure my network? Does the Viessmann Energy Management system work without using the ViCare app? Which devices are compatible with Viessmann Energy Management? How to connect my Viessmann Heating System with the ViCare app? Does the Viessmann Energy Management system work offline? Comments 0 comments Article is closed for comments.