why is my heater blowing cold air constantly?

Hi I have had the same problem on a couple of Mondeos and people will tell rightly you to check coolant levels, heater matrix etc but it is likely that the cable from the temp switch is not fully opening the valve. Check the side of the heater unit to the left of the clutch pedal and you will see two small cogs the top one being atached to a cable. Use a screwdriver to fully turn the cogs and this will open up the valve. With a bit of luck this should give you hot air.
Good luck

Alan

Alan
October 2007

its more than likely that you have air blocked in ur system. try removing ur heater hoses and sticking a hose of water down to get rid of the block of air

Not a mechanic
December 2006