how can i fix my dimplex wht20 heater?

the bulbs need replacing by the sound of it:
Hi, I had the same problem - but eventually found this - If you look at the bars going across the front,under the second one down in each corner is a screw. They are small philips screws - painted black. Undo them and pull the front away. Make sure you take all the coal bits off first! You will need a narrow thread screw in 40w candle bulb. Your flame effect should now work - if not vacuum the fan at the back and gently vacuum the flame effect material strips. If it still doesnt work then you may need a new fan element.
Cheers!

IANB
November 2006