Electric Circulatory Pump

[ridway]

There is a small electric pump that keeps the coolant circulating after the engine has been switched off. Even with the car car locked and bolted it runs on quietly for about 5-10 minutes.

 

The only reason I can see for the use of this is to allow the heater to be used with the engine switched off for several minutes after - perhaps to save fuel?

 

The system obviously cools the engine quicker using the stored heat in its mass to keep you warm. Apart from this, which seems a quirky extra to have, does anyone know if there is another reason for this?

 

Richard

[Ivor_E_Tower]

On diesels, is the turbo water-cooled? If it is, then maybe it's also to protect it.

Strangely, the electric pump runs after the key is removed, even if the engine isn't started - eg my driveway slopes and I park the car against the garage door. If I roll it back without starting it, so I can open the garage door, then when I re-lock the Galaxy, the pump runs for 5-10 minutes anyway.

[Guest p1948040]

two reasons I guess, one practical and one convenience:

Practical - stops the hotspots through 'heat soak' when turning off the engine, especially after a good thrash down the motorway for example.

 

Convenience

When you switch off the engine, the pump keeps the water circulating through the heater matrix and allows you to have up to a couple of hours hot air heating without the engine running...! Very handy in the winter when pulling over for a tea break etc on a long journey.