Jefftlse

the pump should run depending to the (température / 2) if T°c is up to 26°c

if T =26°c pump run 13hours

if T=27°c pump run 13,5hours

if T=28°c pump run 14hours

.....

If T=40°c pump run 20hours

if T=41°C pump run 20,5hours

if T=42°C pump run 21hours

...

how should the pumps actually behave if the temperature changes during the runtime?

Sorry, I forget this point. it's just, 

for all conditions pump should start at 00h00 each day (midnight)

actually I have to set it manually

thanks a lot, 

i will try to understand the logic

I tried to simulate but I don't have Q at 1...

AutoGen_cacfd

This is brilliant and thank you for it but personnaly found it easier to simulate if the timer is not pulsed but only stays on for one minute

Where in the screenshot do you see a timer that is pulsed?