They are designed for being on permanently. Some routers don't even have an on-off switch - gotta unplug them from the wall. However, this is based on normal conditions of reasonable ambient temperatures and locating the device where it has breathing room around it. Installing it in the boiler room or burying it under a pile of stuff could result in overheating.
dw
Hi,
If i powered on the router for 24*7, will it get overheated? Any concern?

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