I just switched out to the V6 volcano hotend a little over a week ago. I'm running modified marlin on a Gigabot printer. 24V 3mm direct. First I changed the thermistor type in the firmware to: 104GT2 thermistor #define TEMP_SENSOR_0 5 Ran PID autotune with these results first KP 71.10 Ki 13.56 Kd 93.18 I started having problems with the controller throwing max temp and thermal runaway errors, even though I'm sure the thermistor is secured properly etc. In the firmware I changed a couple things that fixed that: #define HEATER_0_MAXTEMP 290 //originally 250 #define THERMAL_RUNAWAY_PROTECTION_PERIOD 60 //in seconds originally 40 #define THERMAL_RUNAWAY_PROTECTION_HYSTERESIS 10 // in degree Celsius oringinally 4 These changes seemed to avoid the max temp and thermal runaway errors, but now on to my main problem. When I manually set the temp to say 230, it runs fine and quickly, but when I start a print the temp comes up to about 15 degrees under the target temp and then just hovers there without ever reaching the target temp. I've run PID autotune a few times since then here are my latest results M303 S225 C10 Results: Recv: Kp: 13.75 Recv: Ki: 2.68 Recv: Kd: 17.66 M301 P13.75 I2.68 D17.66 M500 No matter what I do, the temperature still just hovers under target and never reaches it. Sometimes if I go into the Vika control box while its trying to print I can force it somehow, by randomly changing some PID values and then it seems to work. Any idea what I can do to avoid having this happen? Gigabot support has not used your product yet so are clueless on what to do. Thanks I should also mention that I put together an enclosure for the machine and the heated bed is running at around 80C for these prints.