The heating in my lorry doesn't work to the best it can, it lets out a very minimal amount of heat when its been turned to full blast, and it seems to get colder as the lorry is driven, I've had an engineer out for hours trying to solve it and he can't, can anybody help me?

Wendy Gannon, January 2010

If it gets colder as its driven my first assumption is that your thermostat is stuck open causing excessive cooling as you drive. Or maybe your cooling fan on the radiator is stuck on all the time?

paddy, January 2010