Thermal Runaway after the first layer
For some time I have systematically a thermal runaway error after the first layer.
By default the cold fan is at maximum from the 2nd layer to the last layer in the Prusa Slicer setting.
But now, at the begin of the 2nd layer, the temperature is decreasing very quickly until about 190 and thermal error. (I print the first layer at 215°c and the other 210)
I don’t now why I have this pb ?
I managed to work around the problem by calibrating the cold fan around 150 to stabilize the temperature.
But it’s not the default setting in the Prusa Slicer and rather than remoding the gcode of all my files i would like to understand for this change.
Any ideas ?
I have too a min bed temp error when I turn it on cold. However she is in a box in a correct thermal room.
(I have update to the last firmware but no change)
RE: Thermal Runaway after the first layer
Hi, very common behavior. Lower the fan speed in slicer profile or buy hotend silicon sock.
Inproved cooling in newest design simply cools too much and heater is not able to compensate the shock in short time.
Sometimes also helps PID calibration and sometimes replacing the heater (if it is too old and losing power).
Milos
RE: Thermal Runaway after the first layer
We just recently were having similar issue on Czech forum, which finally lead to change of the main board as the drivers were faulty.
even an old man can learn new things 🙂
Standard I3 mk3s, MMU2S, Prusa Enclosure, Fusion 360, PrusaSlicer, Windows 10
PRUSA MINI+ Prusalink + Prusa Connect
RE: Thermal Runaway after the first layer
@milo-v
Yes i understand but why now ? I'm already printing with this setup for some time and no have pb before.
RE: Thermal Runaway after the first layer
@zoltan
I installed too the last firmware for MK2.5S but you say it would be more of a hardware problem ?
Do i have to buy a new card or the support can send me a new main board if she is faulty ?
Thanks
RE: Thermal Runaway after the first layer
Not sure your mk2.5s printer is still under warranty period.
The reason can be any piece within the heating chain ie. Wrong thermal contact between the heating and the nozle, weak or faulty cable after long use, electrical contact issue till the broken drivers on the main board. So a sytematical analysis is needed.
If it worked before with the standard set up profiles I do not think the decrease of the fan speed will be the remedy of your problem.
Look at the video in this thread, is it familiar for you?
You should start with more detailed description of your issue. As I guess you own mk2.5s, did you do any HW change prior your issue appeared, which type of filament is doing your problem, is it from time to time, etc.?
On the thread linked above there were several rounds also with Prusa support involved, they changed the hot end, elaborated and it ended by the main board replacement.
even an old man can learn new things 🙂
Standard I3 mk3s, MMU2S, Prusa Enclosure, Fusion 360, PrusaSlicer, Windows 10
PRUSA MINI+ Prusalink + Prusa Connect
RE: Thermal Runaway after the first layer
No matter the filament, the pb happen every times after the first layer since 2 weeks i think.
If i don't go down the coldfan to about 150, the hotend decrease so fast and thermal runaway error. It's not normal.
So i have to start with what ?
Change the thermistor or/and the heater cartridge ?
RE: Thermal Runaway after the first layer
Let us start first - did you do any hardware related adjustment or did anything unusual happened in short time period prior the issue appeared (hw upgrade, nozzle change etc.?)
Did the reduced fan speed help?
One (probably the best) option could be to contact the online Prusa support chat via logging to e-shop.
even an old man can learn new things 🙂
Standard I3 mk3s, MMU2S, Prusa Enclosure, Fusion 360, PrusaSlicer, Windows 10
PRUSA MINI+ Prusalink + Prusa Connect
RE: Thermal Runaway after the first layer
Yes, i have a error of min bed temp when i start the printer cold. I use the reset button. And i restart the preheating a second time (PLA 215 BED 60)
The firmware is at the last version.
Yes when the fan speed is around 140/150 the nozzle is stabilize (210°c)
I will contact the support. Thanks