UM2 Printhead Fan Problem

[neptuna 1]

Hi friends,

 

I searched the forum and the net but could not find a solution. My fan works normal. When I start printing everything goes right, fan working well. But after awhile fan stops and because of that the filament not getting cooled and when the extruder push the filament it gets thicker in the nozzle and can not get out properly, so less and less filament getting thru the nozzle. After awhile it stops completely and printer just continue to work w/o filament. When the printer finishes and starts to cool down the fan starts to work again after some temperature I guess.

 

Is there a temperature settings to tell the fan to work or is there any other problem? Thanks.

Edited September 8, 2021 by neptuna

[gr5 2,240]

2 minutes ago, neptuna said:

Is there a temperature settings to tell the fan to work or is there any other problem? Thanks.

There is and that could be the problem but unlikely.  It's the same sensor that knows the temp of the nozzle but a different circuit.

 

More likely it's a bad wire in or just above the print head.  Heat the nozzle to 80C so it starts spinning the fan.  Then slide up the black mesh that covers the wiring above the print head and touch/push/play with the cabling.  I believe the wiring is a black and red wire - at least on the fan end of the connector.  Play with things to see if you can get the fan to fail.

 

Maybe also take the head apart (just those 4 long screws).  Don't burn your fingers on the heater block.

 

[neptuna 1]

12 hours ago, gr5 said:

There is and that could be the problem but unlikely.  It's the same sensor that knows the temp of the nozzle but a different circuit.

 

More likely it's a bad wire in or just above the print head.  Heat the nozzle to 80C so it starts spinning the fan.  Then slide up the black mesh that covers the wiring above the print head and touch/push/play with the cabling.  I believe the wiring is a black and red wire - at least on the fan end of the connector.  Play with things to see if you can get the fan to fail.

 

Maybe also take the head apart (just those 4 long screws).  Don't burn your fingers on the heater block.

 

 

Thank you very much for the reply. I will check the cables, there is not much to do otherwise I guess.

[gr5 2,240]

I and other's have had this exact problem and for all of us that I know of, it was in the cabling just above or inside the print head.  So you may be able to debug this just by poking the cabling.  Literally, poking it with your fingers.

 

If you have a friend with a multimeter and who knows electronics, this is a very easy thing to debug and repair.  Otherwise it's a big undertaking (ordering and replacing parts one at a time).

[neptuna 1]

I think I figured it out, the temp. sensor's connector causing the problem. I checked the sensor with a multimeter, the connections and the resistance is OK but the socket it is connecting to motherboard was not that good. I changed it. Now it is working as it should be. 

Thank you again for your time :)