It sounds like system is not that big you might want to look at using a VFD drive and keep your valve simply off an on. It will pay for its self and if you aren't fimliar with control loops it will save you a lot of head aches might be your simplist solution VFD are very simple an kinda cheap an...
The simpliest way to make your fan rotate is to use the VFD analog input write an expression as follows (need your number input for fan analog system: If N7:0 (example) > then 1 Else 0 you can also use this to change color then copy it and go to rotation and copy it and click Visable.
Or you...
