Problems to reach the temperature

Hi there

I have problems to reach the temp before printing (heat-up phase) but only at extruder 1.
It gets allways stuck at 185-190 degres (Set 205 deg).
Do any of you had the same problem?
I measured the voltage of the heater cartriges.
extr. 1= 12.3V
extr.2= 13.9V

i changed the heaters from 1 to 2 and 2 to 1 but the Problem is the same at the extruder 1.
changed the main PCB with the stepper drivers on it but the problem is still there.

What is the temp of your room?
Environment is everything to these machines (not just Velleman)
Check the thermistor is it correctly in the heating block?
Is there any wind blowing on the printer (not the fans on the print head) but coming from some place else.

the roomtemp is 23deg and i don’t think there is wind. the window is closed and so is the door mostly closed. the thermistor i replaced at first when i had this problem. then i replaced the other parts of the extruder 1. all of them.
i don’t think it is also a software problem because i never touched the PID or something in the firmware.

When the extruder reaches its maximum temperature, is it still turned on solid, or is it toggling on and off? (Maybe you can post a picture of the extruder temperature graph from Repetier?)

If the heater is being modulated then your PID settings probably need to be changed. Maybe your replacement thermistor was a different type?

If the heater is staying on solid, but the temperature is not increasing then you probably have a bad heating element or faulty wiring.

Also, make sure the heating element is making good contact with the block.

My spare parts are original.
I made a few measurements between the main board and the extruder but i don’t found out something’s wrong with the hardware or the wiring.
i flashed the newest firmware on the new mainboard but the problem still is there.
When i reach the temp sometime it is stable.

This pic shows the not working start sequence with 205 deg print-temp.
The fan setting in the start g-code was M106 S165

Without de fans it will look like this:

So i changed the start setting to M106 S30 and now it works…
I dont understand this because i never changed this setting before.
When i set the fans on M106 S40 the temp fall down on 190 deg

Interesting. This suggests one of two things: either the cooling efficiency of your fan has increased, or the heating capacity of your power supply has decreased.

Maybe the fan is blowing more directly on the extruder than it was before? Maybe there was something blocking the airflow before that is not now?

If the fan setup hasn’t changed, inspect the electrical connections to the heater for any evidence of overheating. Tighten any screw terminals securely. Do the heater wires get hot near the controller board? Maybe there is a problem in the extruder wiring. The lower voltage you measured for Extruder 1 could be an important clue.

Thanks very much for your ideas Dr_Vegetable.
Sometimes it takes an objective sight to recognize the obvious.
I will check these points and hopefully I’ll find something that could trigger the error.

So i made a few measurements yesterday and now i found the error! :slight_smile:

It was the connection on the Printhead PCB who was anytime a little bit to hot and mold the PCB Pin in the plastic cover of the connector. i replaced the plastic part and now it works better. i think i upgrade to E3D V6 hotends soon… because with the original hotends i have too much trouble. Thanks for your help @Dr_Vegeable