Talk:Radiator (engine cooling)
Electric cooling fan circuits
Electric radiator cooling fans are frequently wired with 3 cables , one of which is ground (?) and the other two are switched (12v? , DC?) turned on by the electronic control unit (relays) to select fan speed apporpriate to cooling demand. Can anybody supply the actual circuit or logic for controlling these 3 fan wires? I cna't find this circuitry anywhere on the internet, or in Chilton's in the local library. Doens't seem like it should be big secret! user:22.214.171.124
- There are two forms of this:
- High power fans, where a simple heavy gauge cable takes the unswitched high-current feed direct to the fan (from the battery or alternator), then a low-current control signal is fed from the engine management system (or just a thermoswitch). These can have several or gradual speeds, all controlled by the one wire.
- Two-speed fans. There are two "power" feeds, one for high-speed, one for low-speed.
- Most fans do have a ground wire, as the way they're mounted on the radiator means that the usual earth return doesn't work.
Andy Dingley (talk) 12:20, 2 March 2009 (UTC)
 says Radiators come in one-, two-, three-, or four-core systems .
Does this mean either that 4 independent radiators are arranged to yield counter-current heat exchange, or does this mean that 4 rows of water tubes pass through the fins and each water molecule passes just one tube before leaving the radiator yielding high air and water flow and high mass?
I think it would be a nice idea to mention at the start the class of equipment that rads belong to, namely "heat exchangers". Maelli (talk) 12:00, 5 February 2014 (UTC) So I did! Maelli (talk) 12:02, 5 February 2014 (UTC)