QIDI PLUS 4 Heater not heating chamber despite setting it to 45deg in Filament Setting

[johnsmith141142143]

So I am trying to print ABS

I want the chamber to heat to 45deg.

I set this in under the Chamber Temp in the Edit Filement Settings/Chamber Temp to 45deg.

When I print however, the Chamber Temp is set to 0 and I am unable to override it.

Really wishing I hadn't purchased this device now. So many issues with it!

[AbidNibBeE]

There are a few issues here. First is that Qidi has hard coded the chamber heater to only kick in after the bed heater comes to temp. That is annoying but livable. When a print starts, Qidi enforces a wait period for the bed temp, but not for the chamber temp. So the print often starts without the chamber heating up first. I pause there and let it heat it up
.
This brings us to the biggest issue, and one you can fix pretty easy. The temperature sensor is a metal fitting that holds a thermocouple, it is located under the top metal frame rail on the right side near the back of the chamber. It is screwed in to the metal frame. That is the dumbest thing Qidi could have done with a chamber heater. The thermocouple is measuring the heatsink not the air. You have to move that sensor. I had to remove the back of the printer to access the wire and feed the slack through till I could move the sensor. It has to stay on the right wall or the wires will get caught in the gantry. I taped it to the auxiliary fan housing on the right wall with kapton tape and 3m double sided tape. Make sure the gantry cannot catch the wire or the sensor.

After I did that the errors disappeared. One morning I was not able to heat over 40C (errors) and my external temp meter read 60C in the chamber. When I moved it the external temp meter read correctly and it heated to 45 in less than ten minutes. It went all the way up to the 60C mark without problems.

[AbidNibBeE]

QIDI PLUS 4 — CHAMBER HEATING SYSTEM CORRECTION AND UPGRADE SUMMARY
Author: AbidNibBeE
System: Qidi Plus 4
Completion: October 2025
Tested working on Firmware 1.7.2

MECHANICAL AND HARDWARE CORRECTIONS

Chamber Circulation and Electronics Cooling Fans

Original: Stock 24 V sleeve-bearing fans with low static pressure and uneven airflow, causing mid-ramp temperature stalls.

Replacements:
• Chamber circulation fan – NMB 12-12032GA-24N-AA-00 Digi-Key PN 12-12032GA-24N-AA-00-ND
• Electronics bay / rear intake fan – Sunon OD1238-24HBXC Digi-Key PN 259-1473-ND
-Provides airflow across SSR, stepper drivers, and mainboard.

Additional changes:
• Printed new rear panel to mount the 120 mm Sunon fan for direct SSR and driver cooling.
• Replaced all fan wiring with 22 AWG silicone-insulated copper wire (replacing 26–28 AWG OEM leads).
• Terminated wiring with JST-VH connectors for serviceability.
• Both fans draw slightly more current (~0.5 A total increase), negligible impact on PSU load.
• The higher current draw can be offset by setting fan idles and PIDs

Results:
• +0.5 V higher terminal voltage at fans.
• Stable RPM and quiet operation.
• Airflow is directional and balanced; chamber temperature stratification reduced > 10 °C.
• SSR and driver temperatures now remain within normal limits.

THERMAL SENSOR RELOCATION

Original location: Sensor clamped to top-right steel frame, thermally coupled to metal and reading 15–20 °C low.
New location: Sensor affixed to chamber circulation fan housing, insulated from frame and directly exposed to airflow.
Sensor type: NTC 100 K MGB18-104F39050L32 (unchanged).

-Result: Accurate chamber temperature within ±2 °C of thermocouple; no false rate faults; piezo sensors operate normally.

FIRMWARE CONFIGURATION CHANGES (printer.cfg)

[heater_generic chamber]
max_power 0.7 # increased from .4
pid_Kp 63.418
pid_Ki 1.342
pid_Kd 749.125
-Purpose: Increased heater output (+75%)

[verify_heater chamber]
max_error 400
check_gain_time 1200
hysteresis 15
heating_gain 0.8
-Purpose: Prevents premature “slow heating” faults and allows realistic PID ramp.

[chamber_fan chamber_fan]
pin U_1:PA4
heater chamber fan_speed 0.3
idle_speed 0.6
-Purpose: Minimizes heat loss during warm-up; maintains gentle recirculation at target.

BOARD FAN CONFIGURATION CHANGES – SUMMARY

Problem: Board fan was undersized and at 100% speed always

Solution: Converted from controller_fan to temperature_fan with PID control tied to MCU temperature.

Key Changes:
• Commented out the original controller_fan section.
• Added new temperature_fan section:

[temperature_fan board_fan]
pin: U_1:PC4
sensor_type: temperature_mcu
sensor_mcu: U_1
control: pid
pid_Kp: 40
pid_Ki: 0.2
pid_Kd: 0.1
min_temp: 0
max_temp: 100
target_temp: 50.0
min_speed: 0.4 # tried .3 but it was clunky. anything below 3 may stall
max_speed: 1.0
kick_start_time: 0.5
off_below: 0.30
cycle_time: 0.035 # ← tried 1kHz (was 0.01 = 100Hz) settled on .035 (350Hz) with trial and error

-Purpose: Fan speed now tracks MCU temperature via PID. It runs 100% only as needed, spins smoothly at low RPM, and is much quieter at printer idle.

Note: This change has a bonus, Board fan was also added to Fluidd’s display list so its speed and state are visible in the UI.

PERFORMANCE RESULTS

Before Fix:
• Chamber stalled at 40–42 °C with “rate too slow” errors.
• Sensor read 15–20 °C low.
• 80–90 min to approach 60 °C (often faulted early).
• Piezo and driver overheating from false compensation.

After Fix:
• Chamber heats from 30 → 60 °C in ≈39 minutes.
• No rate errors.
• Temperature accuracy ±2 °C.
• Stability ±1.5 °C steady-state.
• SSR and drivers remain cool.
• System is quieter overall.

CONCLUSIONS

Root Causes:
– Frame-mounted sensor created false low readings.
– Heater power limit too low (0.4).
– Overly tight verify-heater parameters.
– Poor airflow and undersized wiring.
– SSR and driver cooling inadequate.

Corrections:
– Installed Delta and Orion fans with new rear panel.
– Upgraded to 22 AWG silicone wire.
– Relocated sensor into airflow.
– Retuned verify-heater and PID parameters.
– Converted board fan to MCU-temperature PID control.
– Optimized PWM frequency for quiet low-speed spin.

Outcome:
– Chamber reaches 60 °C in ~39 minutes without faults.
– Maintains ±1–2 °C during long prints.
– Reduced noise and component stress.
– System is reliable, cooler, and stable.

TL;DR: Moving the chamber sensor off the frame, installing Delta and Orion fans (with 22 AWG rewire), and replacing the board fan controller with PID temperature control fixed the Qidi Plus 4 chamber system. It now heats to 60 °C in 39 minutes and holds ±1 °C with zero rate faults.

[AbidNibBeE]

Subject:
Global Start G-Code Workaround for Qidi Studio – Add Chamber Heater Wait to global print start Without Breaking Macros (Untested Fixes)

Summary:
The Qidi Studio slicer does not currently include a chamber-heating wait before print start. The bed heater pauses until target (via M190), but the chamber heater simply begins warming while the print starts, leading to adhesion and warping issues for ABS/ASA users. Without having also made changes to heater PIDs and fans as well as temp sensor relovation it often ends with failed prints due to "heating at unexpected rate" errors.

The steps below describe untested methods for adding a global WAIT_FOR_CHAMBER pause across all materials and projects. These changes may be overwritten by firmware updates or cause unintended effects due to Qidi’s proprietary startup scripts. The safest approach remains to insert the WAIT_FOR_CHAMBER command directly into filament profile start G-code until Qidi publishes official support. I will test this and update when completed, if someone else would like to test this fix, by all means let me know how it goes.

Untested Global Method (Advanced Users):

Close Qidi Studio.

Locate the machine configuration file:

Windows: C:\Users<yourname>\AppData\Roaming\QidiStudio\user\machines\

Linux/macOS: ~/.config/QidiStudio/user/machines/

Open the relevant machine JSON file (e.g., Qidi Plus 4.json) in a text editor.

Find the "start_gcode": entry.

Add the WAIT_FOR_CHAMBER command immediately after the bed heat line (M190).

Example:
"start_gcode": "M104 S{first_layer_temperature[0]}\nM190 S{first_layer_bed_temperature[0]}\nWAIT_FOR_CHAMBER TARGET=60\nG28\nG92 E0\nG1 Z5 F5000\n"

Save the file and restart Qidi Studio. Check exported G-code to confirm the new line appears.

Make a backup of this file before any firmware or software updates.

Safer Tested Alternative (Recommended):
Add the WAIT_FOR_CHAMBER TARGET=60 line to the filament profile Start G-code instead. This approach is isolated to the slicer, avoids interaction with Qidi’s hard-coded start sequences, and will not interfere with printer firmware macros or touchscreen automation.

Disclaimer:
This edit is untested on all firmware revisions. Qidi firmware relies on partially hard-coded macros that may override or duplicate G-code sequences at print start. Proceed carefully, test with supervision, and verify chamber heating and Z-homing behavior before starting long or unattended prints.

[Useronemillion2]

NMB 12-12032GA-24N-AA-00

Hiya - can you confirm what the current draw is for the Original - Aux Part Cooling fan please? The one you have proposed only draws 0.48amps with a nominal input power of 11.52 watts.

Kind regards

V

[AbidNibBeE]

The originals are shown here in pictures. The company who made them is non-existent as far as I can tell. They likely have stock left over, but will be using a new brand in the future. The chamber heater fan was .50 amps and I could not find any specs other than that. The electronics bay cooling fan was .10 amp, and same brand. There is a net increase in amp draw by the two fans together of close to .5 amps, which is not enough to alter the system significantly. The board can do up to a full amp more easily. XH pins are rated for 2 to 3 Amps typically. The firmware changes also reduce real world current draw by slowing the fans down when full speed is not needed.

I am also replacing the stock chamber heater shell with one that relocates the heater to a new orientation in the chamber. I did not like the fan being located above the heater or how hard it was to remove the heater shell. I am also seeing the side walls on the outside near the chamber heater warping. The shell should be printed in PA-GF filament. I also added radiant barrier aluminum tape, and conductive barrier kapton tape under and over where the heater sits in the shell.

Finally, I am editing my firmware change for chamber fan also. It now kicks on when I start the heater from the UI or touchscreen to help circulate the chamber while the bed heats, and establishes static pressure before the chamber heater kicks on. I copied my current working changes again below. I should point out that I did get one error that stopped a print, and it was due to the name scheme of the chamber heater. It should not normally be an issue for you, I tried to print a .gcode file I had sliced before the changes to the .cfg file, and it had a name mismatch for the chamber heater. I re-sliced the file and all was ok.

https://www.printables.com/model/1212350-permanent-bed-platform-levelling-blocks-for-the-qi

https://www.printables.com/model/1150122-qidi-plus-4-lengthways-chamber-heater-casing

heater shell and level blocks by Stew675

https://www.printables.com/model/1382233-qidi-plus-4-rear-cover-high-efficiency

Rear cover by Максим Батурин

Firmware edits:

[heater_generic chamber]
heater_pin: U_1:PC8
max_power: 0.7 # ← INCREASED from 0.4 to provide 75% more heating capacity
sensor_type: NTC 100K MGB18-104F39050L32
sensor_pin: U_1:PA1
control = pid
pid_Kp: 63.418
pid_Ki: 1.342
pid_Kd: 749.125
min_temp: -100
max_temp: 70
target_min_temp: 45
target_max_temp: 65
heat_with_heater_bed: True
heat_with_heater_bed_tem_add: 25

[verify_heater chamber]
max_error: 400 # ← UNCHANGED - already very permissive
check_gain_time: 1200 # ← DOUBLED from 600 to allow much slower heating rate
hysteresis: 15 # ← TRIPLED from 5 to tolerate larger temperature swings
heating_gain: 0.8 # ← REDUCED from 2 to expect 0.8°C per check window (was expecting 2°C)
position_z: 270 # ← UNCHANGED

[chamber_fan chamber_fan]
pin: U_1:PA4
max_power: 1.0 # ← UNCHANGED - keep full power available
shutdown_speed: 0
kick_start_time: 0.5
heater: chamber
fan_speed: 0.60 # fan power while heater is calling
off_below: 0.25 # prevent PWM chatter
idle_timeout: 90 # wait 90 seconds before going to idle, removes excess heat from heater shell and side walls.
idle_speed: 0.4 # gentle mixing at temp, reduces cycling and maintains static pressure.
cycle_time: 0.035 # 28.5 Hz PWM frequency to start : adjust up or down if your fan gives noise or chatter... .035 = 28.5 Hz ... 250Hz = 0.00400 ... 400 Hz = 0.0025 ... 1 kHz = 0.00100

[temperature_fan board_fan]
pin: U_1:PC4
sensor_type: temperature_mcu
sensor_mcu: U_1
control: pid
pid_Kp: 40
pid_Ki: 0.2
pid_Kd: 0.1
min_temp: 0
max_temp: 100
target_temp: 50.0
min_speed: 0.4 # tried .3 but it was clunky. anything below 3 may stall
max_speed: 1.0
kick_start_time: 0.5
off_below: 0.30
cycle_time: 0.035 # ← (tried 1kHz = 0.001 from the original .01 = 100Hz) settled on .035 (~28 Hz) with trial and error

here is the pic of the ramps just after testing this code today. I set from cold chamber to 50 chamber and 75 bed to watch and listen. Perfection. You could turn the heater max power to .8 to go faster, but I do not want warping in the case or heater shell. This took 18 minutes from cold to 50C with a very steady ramp then plateaus nicely. This was with the stock shell and location too. Once the air flow bottleneck is solved with the new shell I expect a 25% decrease in time to 50C

[Useronemillion2]

Hiya Thank you for such a comprehensive reply. I really appreciate your time and consideration. Kind regards Vaughan

…

On Fri, Oct 24, 2025 at 12:39 PM AW ***@***.***> wrote: *AbidNibBeE* left a comment (qidi-community/Plus4-Wiki#96) <#96 (comment)> The originals are shown here in pictures. The company who made them is non-existant as far as I can tell. They likely have stock left over, but will be using a new brand in the future. The chamber heater fan was .50 amps and I could not find any specs other than that. The electronics bay cooling fan was .10 amp, and same brand. There is a net increase in ampd draw by the two fans together of close to .5 amps, which is not enough to alter the system significantly. The firmware changes also reduce real world crurrent draw by slowing the fans down when full speed is not needed. I am also replacing the stock chamber heater shell with one that relocates the heater to a new orientation in the chamber. I did not like the fan being located above the heater or how hard it was to remove the heater shell. Finally, I am editing my firmware change for chamber fan also. I copied my current working changes again below. PXL_20251024_111204409.jpg (view on web) <https://github.com/user-attachments/assets/ee7ea7a0-a991-435e-af17-d3bfec862a5e> PXL_20251024_111221082.jpg (view on web) <https://github.com/user-attachments/assets/b53ca16b-a8c9-44a2-acd7-6453358d1979> PXL_20251024_112256215.jpg (view on web) <https://github.com/user-attachments/assets/b3910b6e-9b2a-4605-87b4-807977bdd140> https://www.printables.com/model/1212350-permanent-bed-platform-levelling-blocks-for-the-qi https://www.printables.com/model/1150122-qidi-plus-4-lengthways-chamber-heater-casing heater shell and level blocks by Stew675 https://www.printables.com/model/1382233-qidi-plus-4-rear-cover-high-efficiency Rear cover by Максим Батурин Firmware edits: [heater_generic chamber] heater_pin: U_1:PC8 max_power: 0.7 # ← INCREASED from 0.4 to provide 75% more heating capacity sensor_type: NTC 100K MGB18-104F39050L32 sensor_pin: U_1:PA1 control = pid pid_Kp: 63.418 pid_Ki: 1.342 pid_Kd: 749.125 min_temp: -100 max_temp: 70 target_min_temp: 45 target_max_temp: 65 heat_with_heater_bed: True heat_with_heater_bed_tem_add: 25 [verify_heater chamber] max_error: 400 # ← UNCHANGED - already very permissive check_gain_time: 1200 # ← DOUBLED from 600 to allow much slower heating rate hysteresis: 15 # ← TRIPLED from 5 to tolerate larger temperature swings heating_gain: 0.8 # ← REDUCED from 2 to expect 0.8°C per check window (was expecting 2°C) position_z: 270 # ← UNCHANGED [chamber_fan chamber_fan] pin: U_1:PA4 max_power: 1.0 # ← UNCHANGED - keep full power available shutdown_speed: 0 kick_start_time: 0.5 heater: chamber fan_speed: 0.6 # ← REDUCED from 1.0 to decrease heat removal during heating off_below: 0 idle_timeout: 60 idle_speed: 0.8 # ← REDUCED from 1.0 for less aggressive cooling at target temp [temperature_fan board_fan] pin: U_1:PC4 sensor_type: temperature_mcu sensor_mcu: U_1 control: pid pid_Kp: 40 pid_Ki: 0.2 pid_Kd: 0.1 min_temp: 0 max_temp: 100 target_temp: 50.0 min_speed: 0.4 # tried .3 but it was clunky. anything below 3 may stall max_speed: 1.0 kick_start_time: 0.5 off_below: 0.30 cycle_time: 0.035 # ← tried 1kHz (was 0.01 = 100Hz) settled on .035 (350Hz) with trial and error — Reply to this email directly, view it on GitHub <#96 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BKV6SPVVNFQ54ILS4B2ZAGD3ZIFXXAVCNFSM6AAAAACJFI2CA2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTINBSGY4DMNZXGY> . You are receiving this because you commented.Message ID: ***@***.***>