How to Increase the Temperature in Your Printer Enclosure

Mod Shop
Written By Matthew Johnson

ABS, ASA, and other "engineering" plastics warp when printed in a cool chamber.

If you're printing them in an enclosure and still getting lifted corners or cracked layers, the chamber temperature is the first thing to look at.

There are two approaches: use the heat your bed already makes, or add a dedicated heater. The dedicated heater splits into buying one or building one. I've used all three across my printers - here's how each works and when you need which.

Disclaimer: I am not liable if you burn your house down or electrocute yourself. Follow this guide at your own risk. If you don't feel confident in your electrical skills or don't have experience with AC/DC wiring and safety, do not start with this project - there are much easier and less risky projects to learn from. Be smart, know your limits, and always add more fail-safes than you think you need.

What Temperature You're Aiming For

Plastics sensitive to low temps

Heated chambers are great for these:

  • ABS/ASA: 45–60°C
  • PA6/CF: 40–50°C
  • PA12/CF: 50–70°C
  • PC: 70–90°C

Make sure to check your specific filament for recommended temps, they can vary by manufacturer.

Plastics sensitive to high temps

You don't want a heated chamber for these:

  • PLA: Ambient temps over 35°C will cause jams and other issues

Plastics that can go either way

  • PETG: Doesn't need an enclosure, but a warm one won't cause problems either

Safety First

You don't need to build your own external heater

Get a BTT Panda Breath. It is a little pricey, but it is safer and more stable than anything you'd put together yourself. It works with Klipper, Bambu printers, and the Snapmaker U1 (probably others). For ABS, ASA, and nylon there's no reason not to go this route - the one thing it won't do is PC because it tops out at 60°C. Details in method 2 below.

If you build one anyway

It needs a hardware thermal cutoff. Minimum, a bimetal snap-disc switch wired in series with the heater's power feed. I'd add a thermal fuse bolted to the heater enclosure as well.

Both of those are mechanical. They open the circuit themselves with no firmware involved. Klipper controlling the heater in software is not a thermal cutoff, and neither is an SSR. Solid-state relays fail shorted more often than they fail open, which latches the heater on: that's the exact failure the snap-disc is there to catch. A PTC heater without an independent snap-disc and fuse is a fire risk.

Other Considerations

What a hot chamber does to the printer

Heating the chamber heats everything in it. I've hit some very tedious issues that took a lot of troubleshooting before I realized it was creep or something else heat-related.

  • Electronics.

    • Control boards and the PSU belong in a vented bay outside the heated volume.
    • Most Voron and RatRig enclosures already separate them — don't undo that.

  • Steppers.

    • Some printers have them in the enclosure, some have them outside. This only applies if they're inside your printer's enclosure.
    • Invest in high-temp stepper motors or watercool them. Without one of those you'll probably hit issues, or you'll have to reduce the current to compensate — which costs you performance.
    • Watch for skipped steps on long prints.

  • Printed parts on the machine itself.

    • If your printer has PLA parts in the heated volume, reprint them in ABS or ASA before you do any sort of heated chamber.

    • ABS+ with CF or GF will hold up better on repeated heating cycles than standard ABS/ASA.

    • This includes extruders.

      • If it's a non-printed extruder, you may have issues with the motor — consider strapping a heatsink onto it or finding a mod that points a fan at it.
      • Printed extruders are doable, but watch out: I like the WWBMG A4T extruder and I think it prints exceptionally well, but I hit major stability issues that I eventually identified as creep. That was with ASA-CF parts. Things near the extruder and motor get very hot, especially when the air around them is also hot. I fixed it by moving to PA6-CF for the motor plate, and using a model that thickened the plate a bit.

      Note the extruder outline melted into the bracket

  • Part cooling.

    • Your part fan will be blowing 60°C air at a 60°C part. Overhangs get harder and cooling performance drops as the chamber gets hotter - that's the tradeoff you're accepting.
    • CPAP cooling is a fix, but a pain to set up. Try higher-performance 5015s or 4028s first before biting the bullet.

Before you add a heater: seal the printer

Chamber temperature is a fight between heat in and heat out, and most default enclosures lose heat at the seams of the panels, not the panels themselves. The aluminum frame conducts heat straight through, and gaps around doors and panels leak warm air constantly. Sealing is cheaper than any heater and it makes every method below work better, so I would do it first.

When my V-Core wouldn't get past 40°C, I used the following and saw chamber temps improve significantly:

  • Reflective insulation on the panels (inside)
  • J-B Weld Red High Temperature RTV Silicone on all the seams
  • Rubber gaskets around the door

Small tip: skip cheap foam tape, because it compresses permanently within a few months allowing the seal to potentially open back up.

Method 1: Bed Heat + Recirculation Fans

Your bed is already a large heater - 300W on a smaller build, 600–750W on larger bed sizes. On its own it heats the chamber slowly, because still air barely moves heat. Adding a recirculating blower that pulls air past the bed's underside turns it into an active chamber heater. How easy this is depends on what type of printer you have.

For fixed-bed printers like Voron 2.4s, this is simple to add. The other benefit is that these can be filter fans (like Nevermores) so you're not only heating the chamber, but filtering the air inside it.

On my Doomcube (Voron 2.4 mod), four 5015 blowers mounted under the bed take the chamber to 55-60°C in about ~8 minutes without a dedicated heater.

On moving-bed printers like the Voron Trident or RatRig V-Core series, you'll need to mount the fans on the moving bed, which is a little trickier. There are mounts for the Trident you can find on Printables, and for V-Core 3.1s, you can try out this mount I designed. It isn't perfect, but it got the job done. On an enclosure the size of the V-Core, it only got me to about 45°C, which is why I eventually moved the V-Core to a Panda Breath.

My fan strategy:

  • 100% during heat-up - maximum air movement, fastest ramp
  • 15% once at temperature - keeps the air mixed without pushing the chamber much past my target
  • 100% for a few minutes after the print ends if you have carbon in the loop, then back down

Klipper setup is a generic fan plus a couple of macros (this works the same on RatOS):

[fan_generic filter]
pin: # your fan output pin
max_power: 1.0

[gcode_macro FILTER_ON]
gcode:
  SET_FAN_SPEED FAN=filter SPEED=1.0

[gcode_macro FILTER_IDLE]
gcode:
  SET_FAN_SPEED FAN=filter SPEED=0.15

[gcode_macro FILTER_OFF]
gcode:
  SET_FAN_SPEED FAN=filter SPEED=0

Pros:

  • Safest of the three: no new heater, no mains wiring, nothing to interlock
  • Cheap: a couple of 5015 fans and printed parts
  • Doubles as VOC filtration if you use Nevermores (or similar) for this job. (A Nevermore Mini uses a HEPA filter for particles as well, but it won't fit under your bed.)

Cons:

  • The ceiling is your bed power minus your enclosure's size and heat loss.
    • A tight, well-sealed enclosure (like the Doomcube, which has air-gapped panels) reaches 60°C with this method, a leaky one won't.
    • My V-Core tops out around 45°C with this method because its enclosure loses more heat than the bed can replace, and it is a much larger enclosure.

Method 2: BTT Panda Breath

If the bed can't get you there, this is where I'd go before building anything. BTT has already sorted out the 300W PTC element, the airflow, and the filtration in one unit. Docs here. I use this on my V-Core 3.1.

It's built for the Bambu P1/X1 series, and BTT documents mounts for those and the Snapmaker U1. For anything else there are community mounts on Printables. Klipper printers are supported, but as of August 2026 the docs list heating control as manual, with automatic operation "coming soon via firmware update". I think that means exposing it to Klipper as something it can control. Right now, mine turns on and heats the V-Core to a set temp when the bed temp is set to a certain temp (all set up in the Panda Breath web console). Fine for me, but something to consider.


Link to the V-Core Mount

You can also connect it to HomeAssistant for automation and logging, which pairs well if your Klipper printers are already in HA through the Moonraker HACS plugin. That's a way around the minimal control you have in Klipper.

Two specs to plan around:

  • It runs on AC 110–220V, so your wall outlet needs to support the amperage this pulls on top of the printer. The kit includes a Y-cable, so you don't need a second outlet.
  • BTT rates the maximum chamber temperature at 60°C.

Pros:

  • Engineered as a product, with safety and standards handled
  • Heater and filtration in one unit, and the filtration is HEPA plus carbon, so it captures particles as well as VOCs (better than a carbon-only Nevermore, unless you use a Mini with the HEPA filter)
  • No wiring to design

Cons:

  • More expensive than method 1
  • 60°C ceiling - enough for ABS, ASA, and nylon, not enough for PC
  • It's still a 300W heater in your enclosure, so it carries more risk than method 1

Method 3: PTC Heater

I'd still take method 2 over this one. If you're going to build this, use a PTC element: its resistance rises sharply at a set temperature, so the element physically cannot heat past it. A plain resistive heater keeps pulling full power when the control fails; a PTC self-limits.

Pick the Curie temperature 10-20°C above your chamber target. An 80°C PTC at 100–200W covers the 55–70°C range. Also, buy the element rated for the voltage you're using it on - you can't take a 24V element and use 48V to power it, but a 48V-rated element at the same wattage draws half the current, which makes the wiring and fuse/breaker situation easier. Check that the outlet and the fuse on your printer's AC inlet can take the extra load.

What the build takes:

  • PTC element with a fan blowing through it - it needs airflow to move heat off the element and into the chamber
  • Bimetal snap-disc in series with the power feed, rated ~10-15°C above the Curie temp
  • Thermal fuse bolted to the heater enclosure
  • Chamber thermistor for control, mounted mid-height, 30–50mm off the walls, out of the direct path from the bed and the fan outlets. Measuring next to the heater tells you nothing about the chamber. The tried-and-true ATC Semitec 104GT-2 is a good pick; I'd save the PT1000s for a hotend rebuild.
  • For AC-powered units over 200W, a dedicated SSR for switching, with the snap-disc still in series on the output

Pros:

  • Closed-loop control at whatever setpoint you want
  • The only route above 60°C

Cons:

  • More parts
  • Real AC wiring
  • Fire risk if you skip the interlock

Happy printing!

Like what I do and want to support me? Buy me a coffee!

Matthew Johnson
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