<p>This has nothing to do with OctoPrint itself, the cause is related to the printer itself, not the print server running the printer.</p>
<p>This is a pretty commonly seen issue (usually seen at heated beds), this is caused by faulty wires/cables or connectors. This usually happens after a vast period of usage. You should (periodically) check the cables and connectors. You could even test if the heater cartridge works by connecting it directly to the power supply.</p>
<p>Considering the limited amount of costs involved to replace the heater cartridge, it is preferred to replace the heater with a similar specification heater element (voltage and power).</p>

CC BY-SA 4.0
2021-09-20T10:41:13.220Z
2021-09-20T13:12:58.603Z
2021-09-20T13:12:58.603Z
0scar
<p>Measure your heater resistance of the heater in the heater block.  Approximate heater resistances are  4.8 Ω for 12 V 30 W and 3.6 Ω for 12 V 40 W.  See <a href="https://3dprinting.stackexchange.com/questions/10695/proper-hotend-heater-for-reprap-x400-pro-v3">Proper hotend heater for Reprap x400 Pro V3</a></p>
<p>Note: you could have a heater measuring the correct resistance but have a poor connection in one of the connectors.</p>

CC BY-SA 4.0
2021-09-20T13:09:40.073Z
2021-09-20T13:09:40.073Z
Perry Webb
<p>My OctPrint and Monoprice Maker Select IIIP (A Wanhao i3 Duplicator Plus clone) were working fine, but suddenly today the hot end won't heat up anymore. I tried disconnecting the OctoPrint USB and resetting the printer power, and it still couldn't heat up the extruder, such as through the filament menu.</p>
<p>But then it got weird.</p>
<p>I left it off for a few hours and turned it on to see if it was getting 12 V to the hot end, and it was heating up again!  So I plugged in the OctopPrint and we're back to square one, the extruder has just been cooling down. I know the thermistor is working, because it's accurately following the temp, such as following the cooldown after the heating stopped working again.</p>
<p>Is it possibly I have a dead hot end and for some reason it temporarily started to work again?  Maybe an intermittent short?</p>
<p>I guess the next step is to open up the base and look at the connector to the motherboard, and or measure for 12 V</p>

<extruder><hotend><wanhao>
OctoPrint suddenly no longer able to heat up hot end / extruder
David Ljung Madison Stellar
# OctoPrint suddenly no longer able to heat up hot end / extruder

(Asked by: username_0 on 2021-09-20)

My OctPrint and Monoprice Maker Select IIIP (A Wanhao i3 Duplicator Plus clone) were working fine, but suddenly today the hot end won't heat up anymore. I tried disconnecting the OctoPrint USB and resetting the printer power, and it still couldn't heat up the extruder, such as through the filament menu.

But then it got weird.

I left it off for a few hours and turned it on to see if it was getting 12 V to the hot end, and it was heating up again! So I plugged in the OctopPrint and we're back to square one, the extruder has just been cooling down. I know the thermistor is working, because it's accurately following the temp, such as following the cooldown after the heating stopped working again.

Is it possibly I have a dead hot end and for some reason it temporarily started to work again? Maybe an intermittent short?

I guess the next step is to open up the base and look at the connector to the motherboard, and or measure for 12 V

**Tags:** extruder, hotend, wanhao

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## 2 answers

### Answer by username_1 on 2021-09-20. Score: 2

This has nothing to do with OctoPrint itself, the cause is related to the printer itself, not the print server running the printer.

This is a pretty commonly seen issue (usually seen at heated beds), this is caused by faulty wires/cables or connectors. This usually happens after a vast period of usage. You should (periodically) check the cables and connectors. You could even test if the heater cartridge works by connecting it directly to the power supply.

Considering the limited amount of costs involved to replace the heater cartridge, it is preferred to replace the heater with a similar specification heater element (voltage and power).


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### Answer by username_2 on 2021-09-20. Score: 0

Measure your heater resistance of the heater in the heater block. Approximate heater resistances are 4.8 Ω for 12 V 30 W and 3.6 Ω for 12 V 40 W. See [Proper hotend heater for Reprap x400 Pro V3](https://3dprinting.stackexchange.com/questions/10695/proper-hotend-heater-for-reprap-x400-pro-v3)

Note: you could have a heater measuring the correct resistance but have a poor connection in one of the connectors.


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