Just a tip guys! 2002 td5! discovery heater wouldnt work took it to one bloke who told me there crap anyway so nothing could be done, second fella said the same and more or less said he would have to take the dash out! ££££, so decide to talk to a fitter who works on lorry's forklifts he is a son of one of my pals,
cut a long story short he come round found the fan under the near side dash took it out cleaned it and bingo the heater works really well so something worth knowing.