# Prusa i3 MK2 Heated Bed Thermal Runaway Problems

I'm having an issue with my Prusa i3 MK2 MMU.

It starts printing just fine, and everything gets up to operating temp quite quickly. However, after printing the first few layers, it seems as if the heated bed can't keep up with the demand, and its temperature starts to drop, first it can barely hold 80 °C and then it slowly drops down to 77-76 °C before the printer shuts off due to BED THERMAL RUNAWAY.

The LED is continuously on for the bed, so it seems to be supplying power when this happens. Setting the printer down from high power to "silent" helps a bit, so could this be that it is not getting enough power?

Ambient temp is around 17 °C.