My heater works fine on full heat, but on cold settings it still comes out warm rather than cold. Car is a mk6 2008 zetec s. It does have air conditioning, but that doesn't work (re gas needed?)

It doesn't appear to have a heater control valve on the bulkhead like my puma did. The car does gurgle once behind the dashboard when you first drive away. Is this the heater matrix? Head gasket hasn't gone and I don't loose coolant.

Cheers,