I have a Mark VIII fan installed with the DCC FK-50P and the fan is no longer turning. I'm not very electrically-inclined, so I'm having trouble diagnosing where the issue lies.

Any suggestions as to how to track down whether the issue is with the fan or the controller? Any help is appreciated, thanks!

 

Job #1. Isolate & troubleshoot:

- remove controller connection to fan.
- Apply power to fan - through a fuse, from the battery.
- If fan turns, it's likely controller (rare) - at this point email Brian at DCControls for additional troubleshooting help, and repair procedures.
- If fan does not turn - go get another fan at a recyclers.

Above assumes you've checked the install completely and have found no obvious problems like a blown fusible link, bad/loose connection(s), etc. It's em-bare-***-ing to blame the controller when it's actually a DFU issue,

Random stuff - does turning the setpoint pot do anything? What happens when you engage the A/C, etc? All these are additional clues.

Controller has "No User-Serviceable Parts Inside" - unless you are a user like me with a controller out of warranty. lol.

MGD

 

Ok resurrecting a very old thread, but my FK35A DC controls controller failed and fan runs at max speed all the time...I just arranged to ship controller to Brian and will see what the story is. To be continued.
By the way thermocouple is working, and input and output voltages appear good, but fan will not turn off even with air conditioning off and thermocouple unplugged. I will post results.

 

Apparently OP amp in the FK35 was bad...so new controller on its way. Replacing with FK45

 

Actually, a blown op-amp, not a bad op-amp. So, given your controller is almost eight years old and, since I told you before your first post here that the controller was damaged by over voltage, what is the reason for your post?

 

Hey not meant as a negative, just giving feed back...Brian could the fan cause overvoltage or is is related to the battery voltage? My connections are all soldered, but I worry that that big Lincoln VIII fan motor may be drawing too much on startup. When it starts the circuitry makes a weird whine noise. But it always has even when the FK35 was installed. Thank you for shipping the FK45 replacement. Nice change with the variable resistor for temp control. Still love this setup....