cooling plant room control ?

I have to write some software to control the temperature in some rooms in a plant , in a room i have a pt 100 and a solenoid valve to the aircoolers that cuts the cooling agent if it's not needed , also i have control of starting the fans of the aircoolers , in some rooms are 1 unit with three fans or 2 units with three fans per unit . Each room has a preset temperature . Plc is siemens cpu 317 w profinet . I would like some starting ideeas if anybody had a similar application powered up .

Thank you a lot ,
Catalin

Done many many times


You could do it with a simple tempcontroller.
with a plc it is easy.
Watch the resoultion of the tempsensor it should be better as 0.1 Celsius.
How about defrost?
Check if fans are running
Temp control with on/off is easiest and you can set the limits, use separate for on and for off. Like 0.5 for off and 0.1 for on. do not use one setpoint with a deviation
if needed more just send mail