CHC&CHC-Pro Heating Core Assembly Guide

CHC&CHC-Pro Heating Core Assembly Guide

Safety Cautions:
Make sure you have ordered and received the correct voltage heater and fan to match the power supply of your printer.

The standard CHC Ceramic heating element maximum temperature can reach 320°C. Exceeding 320 degrees Celsius may cause irreparable damage to the ceramic heating element. CHC and CHC-PRO heating cores are equipped with two types of temperature sensor, 104nt-4-r025h42g and RTD PT1000 class-B. The working temperature of 104nt-4 should not exceed 290 degrees Celsius.

If you are replacing the stock heating block on a commercial printer, and your original thermistor is not PT1000 or 104NT-4-r025h42g. The firmware modification is not optional. It is a mandatory step.

Connecting 12v parts to a 24v power supply can result in overheating, component damage, or fire. If you are unsure double-check the rating on your power supply. Your hot-end and your printer are your responsibility. We cannot be held responsible for damages caused by the use, misuse or abuse of our products.

Warning: Fragile! Please do not clamp or bump the white ceramic heating element with tools under any circumstances.

Used to replace a hotend heating block

1. Heat up the hot-end and unload any filament in it. Unscrew the heatsink. There are heater block, heat breaker and nozzle left together.

2. Heat to the printing temperature, clamp the heating block with an adjustable wrench, be careful not to touch the thermistor or the heater cartridge wires, and unscrew the nozzle with a socket wrench corresponding to the nozzle size. Next gently unscrew the heat breaker with pliers, turn off the heater and wait until all parts cool to a safe temperature before removing the heater cartridge and thermistor further.

3. Make sure there is no plastic residue on the thread and end face of heat breaker and nozzle, if there is, please clean it before installation.

4. Prepare CHC heating core and nozzle, screw in the nozzle as shown in the figure below, screw it to the end, loosen it and turn it half a turn to one turn.

5. Screw in the heat breaker from the other side till finger tight. Make sure the shoulder of the nozzle does not touch the heater block. There must be a gap around 0.5-1mm distance between them. If not you will run a significant risk of not creating a seal during the hot tightening process which will lead to molten plastic leaking from the assembly.

6. Before heating up the heating core it’s a good idea to double-check you are using the correct heater for the power supply you are using.
12V version will read between: 3.5-4 Ω
24V version will read between: 9-11 Ω

7. Heat up the CHC core to 280°C, then wait about 1 minute. Use an adjustable wrench to hold the square side of the core, being careful not to touch any part of the ceramic heating element, as this may cause it to shatter. Tighten the nozzle with a socket wrench, if you have a torque wrench set to 2 Nm.

8. Turn off the heater and wait patiently until the temperature drops to a safe temperature.
Put the silicone insulated socks back on.

9. Apply a small amount of thermal grease on the surface of the heat breaker's mounting threads, and screw the heatsink on by hand. Finger tight is enough no need a wrench. Alternatively, any CPU thermal paste can be used.


Hot-end construction explanation reference video: