Two speed fan control
 

Hello everyone! I'm looking to swap fans in my fc, and I was curious if two speed fans can be controlled with the e420d. I'm currently utilizing wari as that is what I'm familiar with not so much with eugene. I have one wire for fan control which would give me my desired low level, but I would like to have high speed as an option. Have any of you done this? Any help would be most appreciated!

It depends on what you are using all the other auxiliary outputs for. I'm more familiar with the 440d than the 420c, but they both use Wari and you would just configure one aux output to trigger a relay at a low temp, and a second aux output to trigger a second relay at a higher temp.

Another alternative, which is the direction I went, is to use a separate PWM (pulse width modulating) fan controller such as those sold by Derale. They have single and duel fan kits with and without the PWM controller or you can buy the controller separately. The advantage to PWM is that it kicks on at a slow speed as temps start to rise and will increase to full speed only when necessary. You can still use your existing aux output as a failsafe or to force the fan to turn on when you run A/C.