Chamber Heater

This content is for 1.1 (beta). Switch to the stable release docs.

Added in 1.1.

An add-on chamber heater is a separate box that sits in your enclosure, heats the air and filters it. The one HelixScreen understands in detail is the BIGTREETECH Panda Breath.

HelixScreen does not install or configure it. The heater is a network device that talks to Klipper, so Klipper has to be told about it first — and that part is the same whether or not you use HelixScreen. Once Klipper knows about it, HelixScreen finds it on its own with nothing for you to set: the chamber temperature appears in the Temperatures widget, presets can set a chamber target, and a diagnostics card shows the heater’s health.

This page covers getting Klipper to that point. What you see afterwards is in Temperature.

Step 1 — Put the heater on your network

Power the unit up and join it to your Wi-Fi following BIGTREETECH’s instructions (the unit publishes its own setup access point on first boot). Then find the address your Klipper host can reach it at — either its IP address from your router, or the name it advertises, usually PandaBreath.local.

Check from the machine Klipper runs on:

ping PandaBreath.local

If the name does not resolve, use the IP address everywhere below instead. Give the unit a DHCP reservation in your router if you can — the address ends up in your Klipper config, and a heater that moves address goes offline.

Step 2 — Choose which firmware it runs

Two firmwares work with HelixScreen. You do not have to change anything to use the one it came with.

	Stock (as shipped)	DragonBreath (third-party)
Flashing needed	No	Yes, over Wi-Fi
Chamber heating and filtration	Yes	Yes
Filament drying	Yes, from HelixScreen or the unit	From the unit only
Fault reporting in HelixScreen	No	Yes, with a Reset button
Filter-fan speed and control in HelixScreen	No	Yes
Heating-element temperature in HelixScreen	No	Yes
Offline warning in HelixScreen	Yes	Yes

Stock is fine, and it is the right choice if you would rather not flash anything. DragonBreath reports more, so HelixScreen can show more. Everything in the rest of this page applies to both unless a step says otherwise.

Snapmaker U1 owners: skip to the U1 shortcut — your printer has a menu for this and you do not need to edit any files.

Step 3 — Tell Klipper about the heater

Klipper needs two things: a small add-on module, and a few lines in your config. Both projects below ship an installer that does it for you.

You need SSH access to the machine running Klipper.

If you are on stock firmware

cd ~
git clone https://github.com/justinh-rahb/pandabreath-klipper
cd pandabreath-klipper
./install.sh --host PandaBreath.local
sudo systemctl restart klipper

Use --dry-run first if you want to see what it will change. If your Klipper install is in a non-standard place, the installer takes --klipper-dir, --config-dir and --printer-cfg to point it at the right paths.

To write the config by hand instead, copy panda_breath.py into Klipper’s klippy/extras/ folder and add this to printer.cfg:

[panda_breath]
firmware: stock
host: PandaBreath.local
port: 80

[heater_generic panda_breath]
heater_pin: panda_breath:pwm
sensor_type: panda_breath
control: watermark
max_delta: 0.5
min_temp: 15
max_temp: 80

[verify_heater panda_breath]
check_gain_time: 360
hysteresis: 5
heating_gain: 1

Aim to have the unit on BIGTREETECH firmware 1.0.3 or newer — earlier versions are missing sensor fault detection.

If you are on DragonBreath firmware

Flash it first: open the unit’s own web page in a browser, use its Firmware Update feature to upload the dragonbreath-<version>.bin file from the project’s releases, and let it reboot. It carries your Wi-Fi settings across, so it should rejoin by itself. The stock firmware stays on the unit and you can switch back to it later.

Then install the Klipper side:

cd ~
git clone https://github.com/plastikman/dragonbreath-klipper
cd dragonbreath-klipper
./install.sh
sudo systemctl restart klipper

Set the address in the [dragonbreath] section of your config:

[dragonbreath]
host: dragonbreath.local   # or the unit's IP address

[heater_generic dragonbreath]
heater_pin: dragonbreath:pwm
sensor_type: dragonbreath
control: watermark
max_delta: 2.0
min_temp: 0
max_temp: 75

[verify_heater dragonbreath]
check_gain_time: 300
hysteresis: 5
heating_gain: 1

[output_pin dragonbreath_filter]
pin: dragonbreath:filter

The [output_pin] section is what gives you the filter-fan toggle in HelixScreen.

To have Moonraker keep the module updated, add this to moonraker.conf:

[update_manager dragonbreath-klipper]
type: git_repo
path: ~/dragonbreath-klipper
origin: https://github.com/plastikman/dragonbreath-klipper.git
primary_branch: main
managed_services: klipper

The two section names must match. [panda_breath] goes with [heater_generic panda_breath]; [dragonbreath] goes with [heater_generic dragonbreath]. If they differ, Klipper will not start.

Snapmaker U1 with extended firmware

Nothing to install and no files to edit — it is already on the printer.

Open http://<your-printer-ip>:9091 in a browser.
Find Panda Breath Chamber Heater under Snapmaker Components.
Set it to Auto (recommended) or Manual, and enter the heater’s address when asked.

Auto lets the unit hold the chamber itself once the bed is hot, which is gentler on long prints; HelixScreen shows Mode: External while it is doing that. Manual keeps every decision with Klipper. Either works with HelixScreen.

Setting it back to Disabled removes the configuration cleanly.

Step 4 — Restart and check

Restart Klipper (FIRMWARE_RESTART from any console, or the menu in Fluidd/Mainsail). If Klipper refuses to start, the error names the section it did not like — usually a typo in a section name, or the two names not matching.

In HelixScreen you should now see:

A chamber row in the Temperatures widget on the home panel
A chamber target you can set from the temperature panel and from presets that call for one, such as ABS
A diagnostics card under the graph when you open the chamber temperature view — see Temperature for what each part of it means
On stock firmware, a Start Drying button on that card — see Drying Filament in the Chamber

Nothing needs to be enabled in HelixScreen for any of that.

If HelixScreen picks the wrong heater

HelixScreen picks the chamber heater by name, and gets it right for anything called chamber, enclosure, cavity, or named after the appliance. If your setup has more than one generic heater and it chooses badly, set it yourself:

Settings > Devices > Sensors > Temperature Sensors, then use the Chamber Heater dropdown. Leaving it on Auto keeps the automatic pick; None disables the chamber entirely.

Note that choosing a different heater there also turns off the diagnostics card, because the diagnostics belong to the appliance rather than to whatever heater you picked.

Troubleshooting

“Heater offline” in the diagnostics card. The unit has stopped answering on the network while Klipper carries on reporting its last temperature. Check it has power and is still on Wi-Fi. Brief dropouts are normal and are ignored; the warning only appears once the unit has been unreachable for a while. A heater that goes offline often usually has a weak signal where it sits, or an address that changed — a DHCP reservation fixes the second.

The chamber never reaches its target. These heaters are slow, and the chamber warms far more slowly than the heating element inside the unit. A target only a few degrees above room temperature can also sit unreached for a long time. Check your enclosure is actually closed.

The target will not go above a certain point. Both firmwares cap what they accept — DragonBreath refuses targets above 70 °C — and HelixScreen will not offer more than the limit in your config’s max_temp.

“Mode: External” is showing and I did not do that. Something other than HelixScreen is driving the heater: the unit’s own web page, a button on the unit, or its built-in Auto mode. It is informational, not a fault.

The filter fan says “Device” and the toggle will not respond. The unit is running the fan itself — during warm-up, or purging after a heating cycle — and your request cannot override it. It returns to normal when the unit is done.

A note on security

The stock firmware’s network interface has no password. Anyone on your network can reach the heater and turn it on. Keep it on a trusted network, and do not forward its port to the internet.