heaters not hot

[Niall]

Could also try flushing it through, with a hose, or a pressure washer if your feeling ambitious. Then bleeding it after, also would recommend the coke bottle trick to help with bleeding, makes it so much easier, have a search and you'll find it theres been a few on bleeding over the past months.

Silly idea. If your going to flush it, just use a bottle of proper flush and do what it says on the tin. Just remember, there may be crap in there but sometimes thats a good thing if you have any small holes!