BlockingIOError: Error 11 - Printer refuses to do anything, throwing "verify_heater" error

General Discussion
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Printer Model: Creality Ender 3 v2 Neo
MCU / Printerboard: BTT SKR Mini E3 V3
Host / SBC – Raspberry Pi Model 4b
klippy.log (1.6 MB)
moonraker.log (115.5 KB)*
*I don’t know if this will have much use for you, but I saw other posts attaching it so I decided it would probably be of some use

Been dealing with my printer throwing a “verify heater” error, and was led down a rabbit hole of solving this. I have messed with my Verify_Heater settings, trying to figure out or fix the issue (with no avail, of course). After checking my log, I found an issue with the MCU, but I was able to fix it–at least I believe. I looked over frenk.salvi’s issue, being that it threw the same error, and I was able to fix it that way. I also took a quick look over Cowboy124aa’s issue, but their action seemed more like a last resort (of which I am willing to treat as a last resort). However, after my “fix” I received the error: “BlockingIOError: [Errno 11] Resource temporarily unavailable.” In my searching throughout this site, I have not found anything covering this error specifically. A Reddit post states that they had a loose thermsistor, but I have verified that is not the issue.

I would note that I have recently changed the nozzle, and the printer stopped working after the replacement, which could hint at damage (I would hope not, but I don’t mind to fix it) to the nozzle or an issue with something else that the printer does not like. I will need to replace the nozzle with the old one to see if that solves the issue,** but the log seems to be hinting that the issue is dealing with software rather than hardware. As of current, I feel I have made at least some progress, but I am unsure of my next steps. I unfortunately cannot do much with my printer because of this error, and I am relatively new to all of Klipper, which is why I’ve come here. I don’t understand everything, so any help with understanding and also avoiding this issue in the future would be greatly appreciated.

**I will reply with an update if necessary

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Here are the links to resources I mentioned above:

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Hello @stupidcomputer and welcome to the forum!

The heating up of the extruder is quite slow. It takes 3 minutes from about 50°C up to 200°C.

grafik
grafik1225×373 20.5 KB

Usually it is below a minute (on my system from 23°C to 215°C in about 30 seconds)

Do you run a heater cartridge that the PSU is not able to provide power for. E.g. a 24V heater on a 12V system. Maybe the PSU is underpowered.

BTW: You should cool the Pi.

raspberry_pi: temp=66.2
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I do not believe so, my head is stock. (It was replaced a bit ago, but I never had any issues until I switched the nozzle)

Also, thank you for the recommendation; I’ll see what I can do there.

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Then you may check if the thermistor still seated properly.

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If the thermistor is still properly located check for broken strands in the wires to the heating element. Your heater is defiantly not working correctly.

FWIW - A misplaced thermistor is EXACTLY the failure mode [verify_heater] is intended to detect.