Heat switch question

[thebrod]

Hi All

This might seem like a bit of a noob question, but I'm a Patrol noob so here goes.....
I know that the heat switch on my ZD30 makes the engine idle faster, and is supposedly for warming the engine up when its really cold, but what is it actually doing? Is it running the engine with the glow plugs activated or just upping the idle speed?

Cheers

Adam

[the evil twin]

Just raises the idle speed... nothing else.

[thebrod]

Cool, thanks for that. Just curious!