Electric fan control wiring

[Whaler]

Funny thing happened

I have an electric fan with a Blue and a Black wire

Now what would you guys think was the Hot +12 and the GRD

I assumed Black was grd and Blue was hot

UH UH ...LOL the fan ran backwards when I threw the charger on it to check direction. So I did a quick rewire.

Now heres a question for the guru's. I have the hayden temp control. The only wires I am about to use are the switched ignition 12 volts (yellow) A small grd.(black) a 14 ga battery positive (red) Of course theres the output of the controller which goes to 2 fans, I am using one ....orange. This is off a 30 amp relay

So If I want to wire in a fan bypass switch from the toggle on my dash, can I wire into the control wiring?? It seems they have not allowed for a bypass. Its only way to fire the fan is by temp sensor and the electronics behind that.
My assumption is that I have to come from the toggle with a hot and go directly to the fan positive. I have an extra relay wired in the dash ready to go to it if need be. Just was baffled that there seems to be no way of tapping into the temp control to trigger its own relay with my toggel bypass.

A note says that if i want the fan to run after the motor is shut off, I can run that yellow switched wire to a contant hot and it will run on its own depending only on temp setting.

Seems I have to feed the fan on my own with the bypass.

[Jamo]

Yep--you're right. Tap right into the orange/black line from your description.

[Specialk]

Whatever wire goes to the temperature sensor should be grounded to make the fan come on. Take temperature sensor wire and run it to one side of the toggle switch, and run the other side of the toggle switch to a ground. Whenever you flip the toggle switch, it will ground the temperature sensor wire and start the fan.

I hope that made sense

[mr0077]

Whaler, basically, you want the relay to send power to the fan so that the fan can run when the t-stat tells it to OR whenever you want to switch it on manually, right? If so, you need to control the relay to do that. To get the relay to run when the t-stat tells it to, you should run battery power to the relay instead of your yellow switched wire, and have the small black (grd) going to the t-stat. Then, to turn it on manually, have one side of the toggle switch hooked to the small black and the other side to ground (bypassing the t-stat), like Kris K describes. If, for some reason (?) you want instead to interrupt the automatic t-stat control (so it you can turn the fan OFF manually with the switch - NOT RECOMMENDED!), the toggle switch should be in-line on the line to the t-stat, and would open or interrupt the ground between the relay and the t-stat.
Wiring's a pain...LOL

[Jack21]

Ditto SpecialK, above with your setup. Ground the wire going to the temp sender through a dash toggle, then to a chassis ground.

I have a Ron Francis Wireworks dual relay setup with an air conditioner circuit. The air conditioner circuit kicks the fan in whenever the A/C is turned on. Ran the A/C + lead to a dash switch to manually control fan.

[Whaler]

Hi guys thanks for all the replies
Jack it so happens the control also has a wire for AC.
Maybe I will do the same...
I will meter out some of the wires to see what is common on the signal side of the relay coil. I would prefer to use the temp controls own relay not another one from me.

Thanks

Tim

[Whaler]

Jack

Sure as heck , the green wire coming out of the hayden control unit for AC, will work as a manual bypass.
I feed the yellow switched ignition wire, the battery + supply and the green wire ( ac ) 12 volts and the fan flashes up no problem.
Thanks to everybody for input.
Crappy instructions makes no mention of the AC wire's function or a fan manual bypass

Tim