How to best control my 2 speed fan.....here we go

[loganscuda]

Just installed my a/c, I have a 2 speed electric fan (don’t need to know mechanical fan is better. I have no room for it) I have what I Have.
Right now I just have The low speed running off a fan relay with the thermostat in the radiator. I have used this for several years with no issue.
Now I have A/C and need to run the fan with that. What is best way to to this. I don’t have a trinairy switch just a low pressure, but can get it. Do I need a controller like Dakota Digital. What are my options.

 

[Tsully]

This is what I’m running and it seems to work pretty well...as it can be set to control dual fans or dual speed fans. Easy setup as you can setup fan on And off temp along with AC Control.

Davies Craig 0444 Digital Radiator Fans Controller: Adjustable Temperature Range | eBay

 

[Dana67Dart]

In the old days, the ac fan would come on when the AC switch was turned to AC. Relay powered by AC switch. You could probably run a relay off the compressor clutch power, knowing that it might cycle and the fan would cycle too. You could get a time delay relay that would stay energized for 30 seconds.

 

[67Dart273]

^^This is what I'm thinking, don't see a real need for a complicated/ expensive controller, if what you are doing now "works"^^