Z axis

Hello everyone,
I have an Flsun Cube which I have been happily using for more then a year now. I decided to convert it to a core xy/ hypercube mod from thingiverse. I thought I had all the marlin setting correct but when I go to print it will mess up.
The bed will heat up fine then it will home all three axis but when it start to heat the head the z axis starts moving down, away from the head. I have to use the emergency stop to shut it down.
Any thought would be greatly appreciated.

sounds like a wiring or pin definiton problem...

verify both.

What control board...

did you change the controller?
is this different firmware than before?

I have a ramps clone. I did change boards from my original when I was first having problems with the core xy program. Although I have always been running marlin for my firmware. I will switch back to my old board and see how it runs after loading the firmware settings I have now.