I've been meaning to ask about this for a while - TBH, I've been putting it off because I'm scared the answer might be expensive! 
Our washing machine (Zanussi ZWF16581W) gets mould in the drawer & in the rubbery bit between the drum & the door. DH is convinced this means it's not heating but as far as my research has told me, modern washing machines would have an error code if it wasn't. Is this always true or can something go wrong & no error code appear? I've also read about people worrying that their machines aren't heating when they are, it's just the glass doesn't get particularly warm. Is this true?
It's gross & freaking me out & I'm really paranoid that my supposedly clean clothes are actually covered in mould & might end up making someone ill. I have a tendency to be over dramatic... But I don't know if I am or not! 
We don't want to go shelling out for a plumber if there's either no problem or it's something simple that my DIY-handy DH can sort out! Anyone know if there's actually a problem or is having to clean mould out of your washing machine a normal thing to do?!