Webasto Airtop 2000st

[GedR]

I have a Webasto Airtop 2000st, it is working but blows cold air from one vent and hot air from the other vent. I have searched for a solution but have had no luck. Can anyone help?
Thanks Ged

 

[oldiebut goodie]

Presumably you have a Y or T-branch in the ducting if you have 2 vents, check to see if there is a diverter valve on the Y/T that has been closed. Photo of the set-up would be of help.