Good morning peeps,,

this morning and a few other times I’ve had my heater on windscreen hot setting and it’s only blowing cold air??? The temperature gauge is on 90 but still only cold air,,, but if I turn off a couple of times it suddenly then becomes hot and the temp gauge drops to around 70-80 ?? 
anyone have any ideas thanks peeps 

Probably the flap that controls the mix of hot/cold air is getting stuck?

Diagnostic tool will be able to show if one is sticking as it often flags a fault quick.

Cheers mate,,

when at work yesterday I did open bonnet and hold the 2 heater pipes. One was warm the other cold but this morning it was nice and toasty but on the way home last night I was playing around with controls and that seemed to make it become hot as I got down my street and like this morning super toasty