From e3b607ad16e6270b943785da85192c79fa3f7b76 Mon Sep 17 00:00:00 2001 From: Scott Lahteine Date: Sat, 23 Jul 2022 21:14:59 -0500 Subject: =?UTF-8?q?=F0=9F=93=9D=20Troubleshooting=20for=20Heating=20Failed?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- _basics/troubleshooting.md | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/_basics/troubleshooting.md b/_basics/troubleshooting.md index 7f91637d..9897a428 100644 --- a/_basics/troubleshooting.md +++ b/_basics/troubleshooting.md @@ -36,6 +36,18 @@ As seen in this [Chris's Basement video](//youtu.be/H-c8UTg-EMU), the RRD displa ### G29 Probing Failed! Marlin uses the `Z_PROBE_LOW_POINT` value to prevent the probe from pressing too hard against the bed and getting damaged. A value of -2 works well for a flat and level bed, but if the bed isn't trammed yet, the probe may exceed the low point and trigger a "Probing Failed" error. To prevent this from happening, change the setting to something like -10 during initial setup, and then you can change it back after the bed is perfectly trammed. +### Heating Failed! +Thermal Runaway is a constant concern with heaters, so Marlin watches heaters for some common runaway conditions: + +- Thermistor shorted or broken (MINTEMP/MAXTEMP). +- Heating Failed: Temperature is rising too slowly (while below target). +- Thermal Runaway: Temperature is too far from target range for too long (after settling). + NOTE: Thermal Runaway can be caused by a fan blowing too close to the hotend. + +During a first-time setup or firmware upgrade, we recommend leaving Thermal Protection enabled but relaxing the settings. To do this, set `WATCH_TEMP_PERIOD` and `WATCH_BED_TEMP_PERIOD` to longer intervals, such as 40 or 60 seconds. You can increase the `HYSTERESIS` settings to makes thermal protection more tolerant of an untuned PID. You should run `M303` on the hotend and bed as soon as possible, and it will help to loosen up thermal protection until all the PID is well tuned. + +Depending on your setup, you may get more stable heating using `MPCTEMP` instead of `PIDTEMP`. + ### FTDI USB Bandwidth At 115K baud use 167 latency, 192 USB block request. As one goes up the other goes down. -- cgit v1.2.3