I assume you mean EVs with heat pumps? I don’t know of any ICE vehicles that do this, seems inefficient to waste mechanical or electrical energy when you have perfectly good waste heat to use upon reaching operating temperature (though you may need to use an aux heater before reaching that, particularly on diesels)
It’s also an emergency safety heat bleed if your engine is overheating, redirecting some of the heat from that engine block can save your radiator some trouble and keep it going a few more miles
I assume you mean EVs with heat pumps? I don’t know of any ICE vehicles that do this, seems inefficient to waste mechanical or electrical energy when you have perfectly good waste heat to use upon reaching operating temperature (though you may need to use an aux heater before reaching that, particularly on diesels)
Lots of new EVs have heat pumps, in cold climates they need it because the car doesn’t generate enough heat just from running.
It’s also an emergency safety heat bleed if your engine is overheating, redirecting some of the heat from that engine block can save your radiator some trouble and keep it going a few more miles