Put the signal board on the Heating Platform. Heat the signal board on the Heating Platform at 165℃. After the solder balls are formed, turn the power off and cool the motherboard for 5 minutes. Apply some Paste Flux.

Align the logic board with the signal board. Keep heating the motherboard on the 165℃ Heating Platform. When the temperature reaches 165℃, keep heating for 1 minute. This step is to ensure that the logic board and the signal board fit closely. Turn the power off and cool the motherboard for 5 minutes. Then remove the motherboard.