Looking for a solution to provide a momentary switch that closes a remote dry contact / relay for HVAC ventilation

If I understand what you’re describing, I think most people use a Mimolite for the HVAC side, depending on the exact specs of your system.

https://www.fortrezz.com/shop/mimo-lite

Then you can use any battery operated device that can communicate with the smartthings hub for the button/switch that the user operates. The button sends a message to the hub, the hub sends a message to the Mimolite.

Here’s the FAQ list for buttons that work with smartthings. Some of these look more like switches, some look more like buttons, some are handheld, some are wallmount, some are battery powered, some are mains powered. So read the descriptions carefully. Then if you have any questions about a specific device, ask those in the thread for that device, not in the FAQ itself, which is just supposed to be a list with one post per device.

@ogiewon Or some of the other maker folks might have some ideas for other approaches. :sunglasses:

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