Filament cooling fans are not working.

PeterA

Thank YOU I'm on the right track. OK, so now they work?? But the hot end fan spins slowly. However its a 12v fan. (not sure why as the previous owner fitted that)

PeterA

I set them to F250 as it says its the default. ??? Is there a better setting?

PeterA

Sorry for all the questions and thanks for you help. ok so the fans work, except for PO , if I change jumpers they both work, is there a setting that sets the tool fan that could be overriding stuff?

PaulHew

Glad you are making progress!

This is my line for P0
M106 P0 S0 I0 F500 H-1

Duet2's I think have a built in step down, not sure but might be worth checking the documentation in the wiki.

If the previous owner fitted a 12v fan on a 24v output, 1) I am supried it is still working and 2) the possible reason you think your new fan is spinning slowly!

If you connect the new 24v fans to 24v directly does it spin at the same speed as if it is connected to its correct connection. If you see what I mean!

I am not that clued up on PWM like others, just basic fault finding.
I think it will be a case of searching the forum or trying different settings for the F param.

Regards,
Paul.

Phaedrux

Did the previous owner have a separate 12v supply connected to the VFan pin to provide the fans with 12v instead of 24v?

https://duet3d.dozuki.com/Wiki/Connecting_and_configuring_fans

A Former User

@paulhew said in Filament cooling fans are not working.:

Duet2's I think have a built in step down,

Duet 2 has step down to 5v and 3v3. (The Duex expansion boards, and the soon to be released Duet 3 will also have 12v step down for 12v fans when running off 24v)

@petera said in Filament cooling fans are not working.:

I set them to F250 as it says its the default. ??? Is there a better setting?

If you intend to use the default parameter its probably better to not specify it in the config btw. For example, the duet 2 wifi and duet 2 maestro use a different R value in the thermistor config, but if its not specified the same thermistor config is valid for both boards as the firmware will apply the correct default value. Its also easier to read.

PeterA

@paulhew
Thanks I will be trying a few settings.

PeterA

@phaedrux
No he didn't. LOL

PeterA

strange thing is that now the fans all work well on p1 & P2, but on p0 they spin slowly, the settings are as above in the config. Also when using the web interface a can turn them up or down but even on max any of the fans on the p0 jumper turn slowly, I have opted to run my hotend fan off the always on instead of P0, its not fixing the problem but until I figure it out.
What happens if I push the rest button and start again I wonder? LOL

PaulHew

Could be the PWM value for the fan. F parameter
Check this - https://duet3d.dozuki.com/Wiki/Gcode#Section_M106_Fan_On

Another user had a similar issue the other day.