I've had issues with my aircon only working when I was moving but once I had stopped it would then blow out very hot air.
After a bit of research I found out the fan controller had failed and the fan was no longer coming on as it should when the aircon was switched on.
I have a 2.0 TDCI on a 55 plate. This is the model where Ford changed the fan controller and fan. I searched high and low to find the correct fan but failed. Ford only wanted £400 for a new unit.
I then started looking at replacements from other models and found a guy who had used a fan from an earlier Mondeo.
I picked the fan up today and I've fitted the whole unit with the fan fascia and it all works a treat. The wiring connector is different but the wiring colours are the same, black, brown and blue ECU wires. I was lucky in the the breakers had cut off the loom side connector so all I had to do was solder the wires in.
My aircon now works when stationary, it's just a shame the heat wave has now finished.
I hope others will find this of use.