A 12V supply energizes the water pump until the low liquid level activates the float switch.
The pump then switches off.

How do I get the 12V supply to then switch automatically across to activate a 12V fan,
when the pump circuit is open/pump off?

I've though of using two liquid level control float switches, one upside-down, looped to the fan.
Alternatively, could I use a DPDT relay to run the 12V current to the fan when the pump is off?

Many thanks.

 

Yes, you could use a DPDT (or SPDT) relay for the fan.

 

Yes, you could use a DPDT (or SPDT) relay for the fan.

Thanks Zulu.
You also a South African?
Derik

 

Thanks Zulu.
You also a South African?
Derik

Nope.
I live near Los Angeles, CA, USA.

 

Thanks Zulu.
You also a South African?
Derik

Zulu as in GMT?
Max.

 

Zulu as in GMT?
Max.

Yes, I used the military term for GMT.

 

Yes, I used the military term for GMT.

Yeah, I did my military stint with the Royal Signals.
Max.