Chamber PTC heater

A three part chamber heater enclosure for some generic 12V/24V PTC heaters. Print the enclosure in high temp ABS/ASA! Use 4xM3 heat set inserts to attach the cover and 2xM4 inserts to attach the arm.

I am running the fan in the heater module all the time when the chamber heater is to be used, when the PSU for the heater is on, the fan is always on. That keeps the heater housing cooler. 

I am controlling the chamber heater from Klipper, using a mosfet board (12V heater) connected to my controller board. I am using an external 12V PC PSU. (The heater can alternatively be controlled by a dedicated thermostat with a relay).

Sample code in printer.cfg Klipper:
[heater_generic chamber_heat]
heater_pin: P2.7 (replace with the pin you are using on your controller board)
sensor_type: ATC Semitec 104GT-2 (replace with the type you are using for measuring the chamber temp)
sensor_pin: P0.24 (replace with the pin you are using on your controller board)
control: watermark
min_temp: 0
max_temp: 55

Also add a [verify_heater chamber_heat] section and find your values for
max_error:
check_gain_time:
hysteresis:
heating_gain:

You can set the chamber temperature from your slicer and pass it as a variable to the printer start script. Different types of filament will require different temps, so this should be defined for each filament in the slicer.