@Avisheak 

Attempt one solution at at time and observe how it goes:

• Remove the plastic from the router, to allow better heat/air flow (out).
• Reduce the WiFi Transmit Power setting, to low, or possibly turn it off.

I have an Archer C1200 V1, and noticed the router was very hot. I had to use a USB fan to cool the router. However, I decided to investigate further why this is. First, I reduced the WiFi Transmit Power to low and noticed the router is cooler. Next, I turned off the WiFi completely and the router is much cooler. Finally, I reset the Transmit Power back to high and sure enough, the heat was tremendous and a USB fan is needed to cool the router.

I hope the above helps you troubleshoot the heat issue.