pwmconfig command is working well, fan is responding, slowing down stopping and starting again. saving to /etc/fancontrol. /usr/syno/etc/rc.d/S99fancontrol.sh is filled, head changed to #!/opt/bin/sh. Fan is ok, is responding to pwm config. But still no reaction after reboot.
Synoready> echo $PATH
/opt/bin:/opt/sbin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/syno/sbin:/usr/syno/bin:/usr/local/sbin:/usr/local/bin:/opt/bin:/opt/sbin
Maybe I better buy a varistor from Zalman.