with christmas 3 days away this is my worst nightmare.My CH was working fine but all of a sudden it wouldnt come on my water is heating fine but the radiators are freezing i have bled them all to find air in two but it still never worked.At the moment i have it on constant hoping and praying but every so often the 3 lights come on to say the ch is on it stays on sometimes but rads still stay cold.Please help....