Hi I've returned to somewhat my initial script and found that problem is in 'commingFromLow' logic .. in fact I also needed some hysteresis to avoid frequent on/offs near cut temperature so lets say:

I need to run one of fans when temperature reaches lest say 27 degrees but to avoid on/off actions ...

If you need to debug a script a first step is always to look at log (and add some debug log statements when helpful)
Please try below script a couple of runs and share the produced loglines. Also explain what you expected to happen against what the script does (or does not)

Hi
log output:

2021 ...

Hi
i tried to adopt one of script to my purposes:

-- Temp control

local scriptVar = 'tempControl3'

return
{
on =
{
timer =
{
'every minute', -- domoticz events based on timers are triggered once a minute max.
},
customEvents = -- used to increase frequency to once every 30 seconds ...