Zanussi WJD 1257 not Drying?

Even after 2 hours of drying on cotton cycle cloths are still very damp and sometimes the timer when it is tumble drying will drop to 1 minute and it will bleep to say it has finished when seconds before it still had a lot of time remaining.
I have checked the elements with a meter, I get about 256 ohms across one set of elements but open circuit across the other pair.
Is the open circuit faulty?
If so would this affect the timer?

The blower is blowing out hot air but I do not know whether it is as hot as it should be.

Any help would be grateful